I am still suspicious about the intake. Take some brake cleaner and spray the back of your intake and bell housing and wipe it down to where it is clean to the touch. Then drive your car for an hour or so and take a piece of white tissue and wipe along the back of your intake and also along the edges of your valve covers. Also, re-tighten your
oil pan (my bolts became loose after a while of normal driving
). I doubt if your rear mains are leaking yet but you never know. The FE is 40 year old technology.
Clois