What year 360's have the "thicker bore"

4spdragtop said

Karl, I was at a car show and heard Herb Mccandles say 75 and older blocks had the thicker bore.

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That's what I'm trying to determine. I have a bunch of 360 blocks, I'm wondering which ones have the stronger bores. Mine are spread out through the 70's, some early, some middle, some late....