216-235-261 engines sit lower in the back than the front causing any oil escaping from the engine or engine parts to run to the back lowest point. That point is the flywheel cover. Before I went down to your FLAPS to buy a new rear main seal, I would check and be sure no oil is coming from the back of the valve cover toward the back and at the back, check the lower bottom rear corner of the side cover, check the bolts which hold the coil bracket in place. This is one spot more oil than you think comes from. Of course, you want to check the oil pan bolts and the timing cover bolts. Make sure no oil is coming from these spots. If there is still oil coming to the flywheel cover, you may have a problem. A little oil is expected IMHO, but a bunch is not. As said, also check the flywheel. If there is oil on it, you have aproblem, but if it is dry, your oil acculmantions are coming from some of these other places.
Best of luck hunting down you oil leaks.
