I read the thread you did on the crank change, wow!

Did you see oil in the pan under the starter, was there a lot of indication your seal was bad other than the oil usage? There is hardly any oil under my unit and not dripping at all. I am pretty sure my engine has never been apart, but if I attempted this at age 74 and came across the problems you encountered, I probably would not be able finish the project.

I do have a truck repair place here in town that I trust as much as one can trust anyway, if I were sure the seal is why I use oil I think I would just have them replace it.

There was an obvious rear seal leak. Down the oil pan and torque convertor cover. About a qt in 500 miles when I changed it. Big job indeed.