[BruceWilkie]

Originally Posted by Engine-Ear

interesting info...maybe a novice question, but Bruce, et al, does the thickness (any thickness) between the block and bell housing cause other problems with everything behind the plane of the bell housing being shifter back by the spacer's thickness?

The 55-60 block bell face is "recessed" approx 1/4" relative to flywheel flange compared to 61-up. I used 5/16 plate(because it was free) so I'll have a little extra pull out on my convertor...easily shimmed if need be. If I build another I'll use 1/4".