C4 Trans Mount

[rovohn]

Hi
Just about ready to drop the 302/C4 in my Custom,I trimmed the mount holes to accept the new '77 Mustang tranny mount studs but I seem to have a problem,the centre pin that goes through the mount sits about 9/16" proud from the bottom of the mount,I cant really drill a hole in the crossmember as it will weaken it too much.
Any ideas,or is there another mount I can use?
Cheers,John