Power pully woes..

The internally balanced engines, such as the 318s and the early 340s have the "dampeners" with the symmetrical pulley mtg holes.The " dampener" for the cast crank 340 has the one offset hole,and the big" balancing" slug on it so you wont likely interchange it.It should trigger a red-flag in your assemblers brain. On the 360 which was always a cast crank and externally balanced, they continued the offset hole.As to the "balancing" slug on the front "dampener", Im pretty sure mine doesnt have one. I thought I had seen some truck ones with offset slugs. IDK. And yes the "balancing" slug was moved to the convertor and showed up as welded on weights, and in the flywheel as huge drillings.
-So upon reflection, my previous comment in post #5, may have been/probably was in error. Sorry, again.

Edit; Went out and checked; sure enough my 360 has the ugly :dampener on it.