340 ID help please

It's all pretty much been covered. But yeah, cast in June of '71 means it was assembled just after the line was changed to '72 models. If it was a forged crank (and I'd expect it was) than I'm inclined to say it would have had the taller pistons too. The heads could be 2.02 or 1.88s, and it would have been blue.
Like was said, you could never tell with Chrysler.