Everytime i go look under the stang, theres an oily mess at the bottom of he bellhousing. My new clutch is also already staring to slip is the most likely a bad real main seal?
Check out the PCV system first.Make sure theres a strong vacuum and take out the breather element screen and see if it`s plugged up.Clean it in acetone or buy a new screen.
If the PCV system is restricted,crankcase pressure will build up causing a good rear main seal to leak.