Stephan427SC Bingo2 has it right, get a dye kit and run the motor. In 10 minutes or short drive you will find the leak location. If you look up threads with
oil leaks they come from any direction. Kit is about $50.00. Napa has them and some other stores. They also have dye for coolant leaks, trans leaks, rearend, a/c, and P/S system. Yellow glasses look cool too.
Save alot of guessing. Good luck, I's betting on rear main seal or side seals on back cap at top between block and cap. Rick L.