The 360 build that has more turns than Willow Springs

A 91 era MP short block would still be an LA. Mopar didn't even have the production 360 mag until 93
(As per your description of the engine that the 2nd damper came from)
Being as how MP crate motors as I remember we're advertised as "seasoned blocks" that were bored 20-over, that says reman. Is there any cast in dates on the blocks that you have at hand?