.8 is most widely used in the panel repair industry, never used .6 someone who has compared both may lean one way or another. What ever works for you and your machine is the way to go.
The panel crimper is a good tool but it all boils down to what you are trying to achieve. If your going for the unmessed with original look Butt welding would be the go so you can finish both sides of the weld so it looks good in and out. If you want a structurally sound and effective job the crimper is excellent but, and I mean "BUT", the most important thing when welding panels, particularly outer panels is heat control. I've seen many a door destroyed by a well meaning guy with a mig welder putting half skins on. The distortion or shrinkage caused by welding should be addressed as the weld is being done. Use a hammer and dolly to gently stretch the metal either side of a mig weld as the job is being done and keep a cool wet rag handy to minimize the heat ,if you start loosing shape stop and address the problem before moving on this will avoid the tin and a half of body filler you'll need to rectify the problem later.
I'm a bit old school and on any of the older cars if I can gain access to behind the panel I butt weld with the oxy. You can directly work the weld without any build up of weld material and it looks great in and out. Mind you it takes experience to get a good result and not for the novice to attempt.
Any structural work the heat factor usually isn't an issue(floor pans etc) and again depends on what your trying to achieve. I like the crimper and mig for that sort of work.
What has to be kept in mind is that when the steel is heated red hot it expands but when it cools it contracts more than it expanded, hence the technique of heat shrinking. Any weld will pull or shrink the metal around it. The trick is to minimize this or control it.
Don't know if it helped but said it anyway.
Addo

I want to get my drive car more drivable for summer.
Back in the old days we used to put V8 M21's behind our reds with shortened input shafts. Great ratios, loved em. The m20 makes me feel like I'm driving around with a stick stuck up the Kyber pass, very frustrating ratios to say the least. I'm going to throw it as far as I can and put in a M21 just for old time sake. I know they still do the shortened shafts but would like to know who and where?
Any feedback appreciated.
Addo.

Festa, Gympie hey, say G'day to Chardy for me.(it'll either mean something to you or disregard if not.)
Addo.

No money just giving it a good home.
Still there but it's got Alex's name on it at the moment.

Just poped the lid of my racing 202 red. Nothin flash at first glance. Yellow T roller rockers, YellowT valves in a head originally painted fire engine red. (Big ports!).
The question is the pistons have a small semi-circle cut out or rebate to the front and they have the following stamped on top.
RA9096   060
Bot  .003HB
Any one know what they mean. I imagine its been stroked and everything milled to the max to be pushing the compression it was running.
Haven't dropped the sump yet. Cleanest motor inside I've ever pulled apart.
Thanks for any feed back.

Addo,                                                                                               were abouts in the MTNS are you? I live in Springwood            Al

Bullaburra is home, Grey is in Katoomba.

Interesting, but I came to the opinion a long..... time ago that they SHOULD ALL HAVE RED MOTORS IN THEM at very least. Sorry to all you grey sticklers.

Just went and had a good look. The EF seat has about 1 inch clearance from the pillar both sides and 2&1/2-3 inches from the door itself. the line of the seat is spot on for the shape of the sill. (Thats 25mm and 65-75mm for any new age Guys and Gals out there)

Addo do they match the angle of the door well and do they foul on the door at all ? Ive been told they fit well in my chev which is a lot larger and I hadnt considered one for any of the old Holdens..

I'm sure I've got good clearance, I was surprised when I trial fitted it how well it sat. If I get a chance over next day or so I'll take some pics of how it looks and post them. It beats the hell out of what I was sitting on before!

My first car was an EJ (sorry guys) and I bought a 132.5 from a guy up at Medlow Bath in the Blue Mtns I think this thing was original and unmessed. He was using it on a saw bench to cut wood. (of course!) It was snowing the day my Dad and I went to look at it. This was back in1977 It was the lighter colour.

Not sure about the commodore seats but I've got a an EF falcon bench seat in my sedan, the width is great, you can take the headrests out and fold down the centre armrest and it looks somewhat like low back buckets from days of old from outside when your cruisin.
I've got legs like a spider and the seats right back so I don't have a problem with the floor shift fowling the seat. I've picked up another out of an EB and it seems to be the same style and dimensions. I'm going to have it retrimed and fit it to my next project.
Just a thought.
Addo.

Whew at last! a grey motor that actually looks like I remember them. Thank you!

To bad your not in Sydney, I have a Cigweld 250 for sale 240 volt. I have Three welders but only want two the others are migomags. Not bad units worth looking at and not that bad on price.
I might whack it in the for sale section some one local might be looking for one as well.
It would make you cringe but I just threw out a esab 180. couldn't give it away. It was an old unit and three phase but it did work. It's in the scrap bin out the side  of my workshop. :-/

I've got a 202 that came out of a methonol burning track car. It was running triple, dual throat mechanical injection. Has a cam that would kill, roller rockers, high volume sump with a pick up hosed from the lowpoint running through a filter mounted to the skirt of the car. It only did a half dozen laps since it was built and I was going to wind it down a little and put it in the FC but when I did a compression test cold and on the bench it read 250 psi per pot!!! That is a lot of compression considering the standard high compression 202 runs about 180 to185 psi (I think from memory). I changed my mind when I found this out and relised a standard inlet manifold was left with about 2 mm all round from falling in the head. I am going to pull it apart one day and see what it is really made of. You've got to love a really hot red!

must have been a while ago.

1982 if my memory serves me right.  

Thanks Mark, I've already picked up a VS series 2 with low kms for a donor car and am looking forward to putting it together as soon as I draw breath from my current workload. I haven't got the front end yet but I really want one! they look tops. What sort of front end is in the EH?
With Thanks,
Addo.

When I was a young bloke we used to put illegal red motors in the old girls and paint them original "grey" it didn't look much like your picture at all. (I did a lot of reds painted grey) If you did it with a 2 pac PPG colour you could have anything! The gloss finish would be way of original and PPG sucks. I've been in the panel industry for 26 years and own my own panelshop and I am not impressed with them at all. I could write a book on stories with a bad ending concerning them.
By the way the first copper that saw one of our reds painted grey said "thats a red motor painted grey!" and defected us on the spot.

Interesting variation on a panel van/ station wagon.
Going back a few years I found a totally decimated 3 door wagon/ panelvan in the bush. It was a station wagon on the left side and a panel van on the right.
The only thing I could salvage from it was the id tag. I've still got it somewhere.

What about the sedans? I've got a set off a 59 but my other 2 58's didn't have them??

Was poking around my spares car the other day and looked in the boot. There's an old Grey all pulled apart in there. I've had the car for 5 years, the guy I got it from had it for 3 years and before that it sat in a corner of a panelshop for the best part of 12 years. That makes it 20 years less worn out than some! A mate of mine said it is getting harder to find original blocks these days. (I've always played 'red motor in early holden'). This "MAY" be a sound unmessed block, crank & head for a rebuild if anyones interested. It's just sitting there. You want it come and get it.
Blue Mtns NSW.