Found my dads original 1971 duster!

All correct sir. But for testing purposes, he needs to find out. Plus it needs more than 4 degrees.
I agree, it definitely needs more than 4 degrees. What I was suggesting, was rather than getting a base setting of 16 before firing it up, since its already a running engine, to get someone who knows what they are doing and just get in there with a light and time it properly. Or do you think that setting an initial timing would be a better way to go, kind of like starting from scratch?