"LA" engine?

I have never seen anything straight from Chrysler as to what LA stood for. Although I have read both "Lightweight A" and "Late A".

It is very likely similar to the Ford 351M engine. Some say the M stands for "modified" some say "Midland" some say "Michigan", but Ford's response is they simply threw a letter behind the new 351M to designate it from the already produced 351W.

I suspect Chrysler did a similar thing with the LA.

I am not arguing the point, just throwing it out there. Does anybody have any evidence straight from Chrysler?