318 rear main seal replacement

I installed a shift kit a few months ago in it haha, then found that the seal is leaking, I think. Still have to pinpoint it but it shouldn't be that bad if I do. I put a drain plug in the back of the pan when I did it as well so that should help.
Just a bolt with a washer ontop to pull the new seal in or something like that should work for the one in the case.
The rear seal is leaking..again....so I have to replace that too haha.
Thanks for the help.
I'm located about 30 minutes out of San Francisco