The L72's in 69 got different codes because something on the engine assembly was different, probably ex manifolds, the most common reason. That's why the L48 (SS350) engine in 69 is a different code in the full-size cars versus the Camaro/Chevelle/Nova (rams horn vs log style).
I've heard several people with more knowledge than me dispute that article. And it was Fran that later found the bill of material that showed it was a 396. I may be mistaken, maybe it was a L88 intake (cause the carbs were installed at the assembly plant).
Several people have found 396 MV blocks (including Stan), and noone has yet come forth with a 427 MV block. Someone was blowing smoke in that article.
