Oil leak trouble

[Hatterascal]

I recently replaced the oil coolant lines and oil cooler on my '95 6.5TD due to leaks around the fittings. I cleaned off the bottom of the engine and rechecked for leaks while running the engine. Now I notice a very small drop of oil come out of the hole in the bottom of the bell housing. I can actually see the torque converter spinning through this hole and a small drop forms about every 5-6 seconds. This is the only oil leak I can find and only when the engine is running. My concern is it's the rear main seal. Are there any suggestions I can tackle before taking it in?

[JohnC]

Could be the main seal. Also, could be fuel running down the valley and the back of the engine.