a500 ?

This is a great swap. Good enough. A spruced up a 318 for street/cruise...
Expect to spend time with maintenance anything over 320 ft. Lbs. Be well advised from a friend at a Chrysler dealer or your local transmission shop (above). Take a look and see what gear vendors has to offer.

Knowingly have seen this in a mild turbo Slant six build.

"put it in. break it. put in another" -Your Mom