I dont think any 6 had the same bell housing bolt pattern as the small block. However, you might be able to just swap out the 6cly bellhousing on the ****** to one that will fit a 302. I'm not sure if a 6cyl C4 is any different internaly.
The C4 had a removeable bellhousing, so you'd need to find the engine plate, flexplate, torque converter, & bellhousing for a V8 C4 - it should bolt up.
I took a C4 w/ bellhousing and torque converter from a late 70's Granada with a six, and bolted it up to a '67 289. I left the origional 289 flexplate on the motor.
Is there a source for info to learn what goes with what? Ideally, I'd like to get a donor car to strip, but that may not work out, so I'll have to mix and match.
heres a good place, just ask. See how many replys you got. Fordbarn.com is obviously about fords, but it usualy takes longer as its not as big, and there are a lot of the same people here and there
What would cause it to be out of balance? I am doing kind of the opposite, I have a 240 six in my truck and have a C4 with a 302 bellhousing and flywheel. i always thought they were different until just now.