I 'll bet your
oil leak is coming from the front intake-manifold end gasket. Where the gasket makes the turn around behind the distributor is notorious for pinching out and leaking. A leak here will run down behind the distributor, thus giving the false impression
oil is coming from the distributor base.
I resort to using "gorilla snot", officially known as 3M Weatherstrip Adhesive, to glue the gasket to the block and keep it from pinching out as I torque down the manifold. So, take a good look at this area before you go any further.
Good luck