I’ve got a 1964 394 with auto trans and would like to put a manual transmission behind it. I found a couple of 1962 394 flywheels. They both have a cutout on the backside I’m assuming for balancing.
• question 1- do 394 flywheels interchange all years?
• question 2- do the flywheels bolt up any of 6 positions? The holes look symmetrical and I don’t see an indexing pin hole.
Thank you, Charlie

 

I don't know why, but the Olds parts book lists 1962 and 1964 Flywheels as different part numbers.
Most aftermarket flywheels of the past didn't make that distinction.
All you can do is try it.
There will be one bolt hole which is slightly offset, so the flywheel goes on only one way.
You will need longer bolts. Bolts from a 351 Ford will fit. ARP makes them.

The crankshaft will need to be removed and drilled for a pilot bearing too.

 

Thanks