I recently put my car back on frame after extensive work on flooring
While I had motor out 396 I took pan off and did some snooping.
I checked bearings and replaced the oil pump as I had a new one.
I put new gaskets down and replaced pan. after installing motor
I noticed a slow leak at the back of rear seal to floor Not bad. I wiped it up
Waited about a month and went back another small puddle
The kicker is I have silicone on 4 corners NO OIL OR FILTER YET
Yet there is a leak. Its the most baffling thing I ever seen????
Any ideas would be appreciated There is no fluid in transmisiion
Other than convertor and the inside of belhousing is powder dry.
I dont want to finish it if Im going to have to turn around and repair it????
ANY suggestions would be appreciated

Probably from oil in one of the pan bolt holes. Put oil in it, start it, then see if it leaks.