Interesting find

[feller]

So I bought a parts truck and couple of years ago. It had a locked up engine, that i finally decided to tear into, I found out that it was not only the original motor (big surprise) but that it was a 307 according to the casting numbers, also the heads are from a 76, if im reading them right. The motor is a 71(again if I'm reading it right). Any chance this was built to address the 307 flaws?

Also I cracked open the rear differential, ring gear said 14 43 so that's 3.07, right? What a coincidence.