which year best 360 to start with?

Ron, I have a 360 with a '70 casting date and had it sonic checked and I have a few from the mid to late '70s and one from '88 and they were sonic checked too and there is no real difference between the blocks to even report. This doesn't mean that you can't sell your early block to someone that still thinks the early ones are better. There are a ton of guys out there that stilll think this is true, why do you think I bought the '70 casting date block? I also used to think the early blocks were thicker until I had it and other early blocks tested sonic tested. The only thing that might possibly be better with the early blocks is the nickel content and alloy of the iron used. But to confirm this samples of the blocks would have to be sent in for analysis, which I don't think it is worth it.

Chuck