Well, it was the 48th transmission built on Wednesday, April 5th, 1978. I can see that much.
So, definitely not an early style. I'd say it might be a desirable trans and could have good intenals, but, I can't really read the 7-digit identifier number that tells me more about the application.
***EDIT** There is a # 4058114. Looks like 400 engine with 4bbl, passenger car type, but for station wagon, not built for California (49 state). Doesn't look to be a lockup type trans.... so yes, excellent builder.