I'm seeing a puddle under my '59 and it kinda looks transmission related, this is a low mile car that might have already had a transmission rebuild(or shitty original install with a bunch of missing and loose bolts). I did goop all gaskets and also between the case and cluster shaft (a spot where muncies leak). This is starting to look like the case itself has a leak, i wouldnt even imagine this except the casting is one of the shittyiest i have ever seen, there are patches in the casting that are really ugly. If this is the case i'm at the point i will t85 and switch to the lincoln 368 that i already have an adapter for 

I ran a T86 a and a T85 in my car with no problems leaking. Some pics would be helpful.

Durham Missouri

You don’t mention if this is an overdrive transmission or not.  If an overdrive, then the seal at the electric solenoid could be leaking.  That particular seal on the T-85 in my ’55 Customline was troublesome in that area and I eventually put two seals stacked on top of each other at that location and haven’t had any oil seeps since.

Lorena, Texas (South of Waco)

Yea it is an overdrive....I may look at that, i havent got the OD working since i put it together but i think that is a wiring issue and it is either too cold or raining to crawl under it on the street so i've just been driving it, so i guess i should since it could wear in the new seal.