It's not the bolts that have to fit through the holes, its the spacers. Check out the size of the holes in the FC crossmember.
A rather lengthy explanation follows
FC mounting consists of 3 rubbers and 2 spacers (the various colours & lengths have been discussed on numerous occasions). Suffice to say it is not the easiest thing to put together right, because the principal idea is that the crossmember "floats" between the lower 2 rubbers, but the retaining plate is held firm by the spacers in the middle. Check out figures 3-5 and 3-6 in the workshop manual for a clear picture of how the thing is supposed to work. Torquing the nuts up correctly also takes lots of effort & is fiddly.
If you do not drill out the crossmember the spacers lock on the crossmember and the rubbers are virtually useless. The results will be that road shock and noise is transferred from the crossmember into the body of the car which is undesireable.
HR mounting consists of 2 rubbers and 1 spacer - very easy to put together and now the crossmember simply has a rubber sandwiched between it and the subframe.
You can see why the HR mounting system is desireable, it is much simpler and easily assembled and tightened.
Every HR front end I have put on an FE or FC I have used the HR mounting system.
Answers to your questions;
You probably have to buy the FC kit to get the lower rubber insulator new, or use a second hand one.
I don't know the code A1005 - It may be their own code or maybe a Bursons/Repco code or something else again.
Ken