Motor oil leak

Hi, I recently did some engine work on my car listed above.I installed some bearings. When I put everything back on and added its oil, transmission fluid, and coolant, I go and started up and everything seemed fine until a friend of mine told me to stop the engine. So I did and he told me to look under the car and there it was a oil leak. Now I am not talking just a few drops am talking more long almost like if I was draining the oil. It was coming down between the engine and transmission so I thought it was the rear main seal. So I took replaced it but it still leaking from the same place. What can it be?