I was told tonight, by the person who is putting a 263 into my 46, which like your car had the smaller engine, that putting a Dynaflow drivetrain in place of the whole manual system is a nightmare and a real pain in the tush. Better to stay with the manual trans, unless you are really good at fab work. Machining a crank is an option, but you need to be sure they are qualified, otherwise you trash a crank and start another search, and spend even more dollars.