LA small block timing is suddenly way off

Not trying to argue, I'm the novice here, but even a reverse rotation engine would have a normal rotation direction,

Reverse rotation engines use the very same main and rod bearings that normal engines use.

About the only (very minor) thing rotating one backwards causes, is if you are trying to resolve a timing issue, LOL, you need to rotate it BACK far enough, that you can then rotate forward again far enough to take the slack out of the timing chain.