Which 351w block should I look for?

[HotRoddin]

Originally posted by MidNiteBlu 5.0
If you cant afford an SVo block then the 69 351 block is sopposedly one of the strongest.

The conventional wisdom as far as i know it has always been that the blocks after late 70's had to thin a cylinder walls to be any good for hi po applications ... I had a 83 block sonic checked about two months ago and the shop said it was the first 351W block newer than 79 he'd checked ... it came out according to him, substantially thicker than any 351W block he'd ever done. So much for conventional wisdom ?? The other beef people have with later blocks is that they are much lower in nickel content, which makes them more prone to cracking.
After seeing the thin wall myth blown out of the water, now i seriously question the nickel content theory ?? I'd love to see an actual test done to put that question to rest one way or the other ... I'm begining to wonder if it was all started by some guy who had a garage full of real old 351 blocks ?