Rear main seal

[squawk7700]

Just had a rebuild on my 2000 GT engine and all is good now and no water loss anymore. BUT...I'm was getting some significant oil leaking from in front of the flywheel after the rebuild (it never leaked before the rebuild). So went back in and replaced the aftermarket seal that was put in with (I think) an OEM seal and most of the leaking has gone away, but still a few drops coming out after a run. Any ideas why this might be? Thanks.