[plugeye]

R u 100% sure its primary fluid and not tranny fluid. I think no matter where the leak is, it always ends up to the bottom of the primary like that. I chased a oil leak thinking it was the primary but it turned out it was the transmission quad and main seal. Change out the primary fluid to atf so he can make sure that's the oil that is leaking since it will be red

same here.
smell it to identify

 

[plugeye]

cant answer all your questions but
i believe 36 is the leaking seal. it seals between the 5th gear shaft & the countershaft. when i replaced it, i picked out the old one & used a modified PVC pipe to install the new one.