A904 to 360

The only cranks with the small diameter converter hole are the '60-67 slant 6 and the '64-7 273's. If you pull those early engines out and replace it with a '68-up version or a different size early engine (ie. 318) you'll need the bushing to take up the space between the converter hub and the edge of the crank hole or the converter won't be centered. (unless you're really lucky!) The result of not doing this is usually a broken flex plate and/or engine vibration.

OK, I'm learning stuff here as well.

As far as I know, the engine in my '65 is actually a '67 from what I was told. So really there is no difference as far as the tranny fit goes. I assume that the tranny in my car is still a '65, again it doesn't seem to make a difference. But the 408 is a '92, so I can still use my current tranny as long as I get this bushing?

Please say yes, I'd like to drop the 408 in before I upgrade the tranny and rear end. Just for chits and giggles. It might make me break in the engine and cam easier if I'm afraid of blowing up the rear end. :-D