Firewall/Distributor clearance

[inetquestion]

I noticed a weird difference between mine and a friends 69 regarding the amount of clearance between the distributor the other day. I've got a stock 307 with an elec disctributor which I had to modify the firewall to allow it to fit. He's got a 350 with the same type setup and has about an inch of clearance with no modification at all. I was under the impression that all the small blocks were basically the same. Also checked his motor mounts and they appear to be in the same position as mine... any one seen this before?

http://69camarorestoration.com/modul...serialNumber=2

-Inet
69camarorestoration.com