Chalk marks

[FCwagon]

Having read some other interesting posts regards assembly  line chalk markings, I came across some on my gen. 51,000 miles FC on the weekend. It's fairly advanced in the pull apart process now and I only have the diff and tail llights to remove before it's just a shell.  
The rear doors look like they've never been touched since new and have chalk marks which match the door trims. It's a 50 in a circle with a 1 or / beneath.  ??? The front doors also have chalk marks but these don't match the trims nor the rear doors. Both the front armrests have and 82 scratched on the inside.
Another interesting thing is that one rear door has a tar board stuck on as sound deadening and the other has spray on body deadening (as do the front doors). They all seem to be original doors so - was there a change in the sound deadening method and the tar board one was just a left over?
Leigh

[fe2ek]

Whilst i was putting in a radio in my FC on the weekend I came across some chalk/crayon marks inside the front left wheel well,just above the floor seam.I will try and take a photo.

Cheers Geoff

[gp]

Leigh,
they did change from tar paper to spray-on deadener. I'm not sure when that happened.

Maybe Ken knows the answer to this??

Cheers,

Graham

[RET]

The change from tar-paper to sound-deadener is mentioned in one of the GM-H Service Bulletins.  I should be able to find it without too much trouble tonight.

cheers
RET

[mcl1959]

Yep, service bulletin No H147G dated June 1959, advises that spray on deadener replaces bitumenous board.
Obviously there would be some cars with a mix of both at around the changeover time

Ken

[FCwagon]

Thanks guys, I reckon I know why they changed to spray on deadener - The tar board just fell off in one piece as soon as I touched it.
Plastic seals on the doors also were 3 different colours - blue, white & grey and were stretched like a drum skin.
Another wierd thing I noticed was the gasket on the dipswitch was made from headlining material. (cheapskates)
Leigh