Another possibility to consider, the rear main may not be leaking very much. A small leak there is almost expected, however a major contributor to the leak could be the side cover or the tappet cover gasket. I replaced the rear main gasket on my ‘51 this spring while adjusting main and rod bearing clearances. Now it appears to be leaking like a screen door when in fact it’s the side cover gasket. The lower left side corner is a prime suspect. The engine sits at an angle and oil pools in that corner, leaking and looking exactly like a rear main leak. Same goes for the rear of the tappet cover.
The only way I’ve found to be sure is to pressure wash the engine really well, go for a drive and when checking for leaks pay particular attention to the area just above the starter. Any oil there is from one of the aforementioned gaskets.
Good Luck
RonR
Thanks. I guess that's what I need to do is pressure wash the engine and get all the gunk off and then see if I can see where it is coming from.
