Not sure what year V8 or what tranny you want but 6 cyl and V8 bellhousings are same from 1963 on. Your 6 cyl BH will not work with V8 if that is what you are thinking. The pre 63 6 cyl and V8 bellhousings mount to frame the same and clutch pivot is the same but not bolt pattern. It is ALWAYS ALWAYS better to mock it up before installing motor swaps/crosmembers. No need to fix firewall if you mock up with THE engine or a spare block. You will probably have to modify driveshaft length, $40. Those tubular, bracketed, eng crossmember mounts are best.(I prefer the side mount motor mounts unless you use an older V8, then no choice)$55. Transmission crossmembers come in the tubular/bracketed type also,$45.(older truck bellhousings come with side mount pads) You can bolt those X-members all up to engine and tranny, then mark them for frame drilling. This will be fool proof. You can screw up measuring, estimating, and forgetting things, like starter clearance, linkage, exhaust, Distributor (as mentioned), fan clearance, transmission clearance, engine angle (level carb), pinion angle, steering clearance.... Do the extra work, save a lot of headaches!!! Front clip comes off in one piece, piece of cake. Much easier to work on that way.
