Aside from the steering box, which is a problem for any V-8 in our cars, the biggest decision is how high to mount the motor. If you mount it high there are no problems with the oil pan, etc., but you will do a lot of firewall/floor work for the transmission and driveshaft clearance. If you mount it lower there will be less floor work, but much more work in the oil pan/oil pump area.
Good luck if you go for it.
Marty
PS - no matter what route you go you will be making custom motor mounts and transmission crossmembers, not to mention a driveshaft and doing something for the emergency brake, along with probably putting in a different rearend (because the stock one is geared way lower than you want with a V-8).