The clutch had started slipping so out came the engine.
When the engine separated from the bell housing about a quart of engine oil poured out. The drain hole was plugged up with a piece of a cut off bolt and oil sludge.
The engine wasn’t using much oil (especially for a Detroit) so it appears the rear seal has a slow leak that couldn’t drain out the bottom
and built up inside the housing. Check those drain holes.
