Something up front is leaking bad. Not the Dipstick Tube.

Tranny is out. Photo posted. Is the seal just 'popped out'?

Does the seal look like the Crank seal? To me it looks like one seal inside the other. Photo also posted.

It's your "front pump seal". W a small screwdriver/hammer at JUST THE RIGHT ANGLE so as not to mar the aluminum housing cave the seal inward at various points around the perimeter until it is loose enough to pull it out. Pack the rear of your new seal with vaseline to hold the spring in place then tap it in evenly using something flat around the seal at various points. Be sure to get it started evenly (& keep it even as you go around tapping it) and end up w it it flush w the case. Lube the TC snout w trans fluid

Only thing to add is check the mating surface of the Torque converter and make sure it's not scored...With the seal looking like that I'd probably check the metal pump/converter bushing and see how that looks also but then you're getting into the internals of the trans and some won't get into that..

The seal in your trans now is made of Nitrile "rubber". That stuff is bulletproof. If it is really leaking from there, you have a bushing/hub problem. The new seal you show is made of silicone "rubber". O.E. to be sure on early T.F., but I would not use it.
Pat

Yes, there's a bushing in the pump that the torque converter hub rides in.... Usually this bushing wears out and the front seal will leak...Unless you find proof of the seal itself caused the problem as stated that's the bushing I'd be checking on..

Couple more shots

Should I be sending this out to a shop?

...OK, I'm looking at the pic of the TC snout....Is that orange paint sprayed/chipping off the sealing surface of the snout or just the pic ???? Any flaking paint won't seal...If it was painted over the sealing area of the TC snout sometimes it'll chew up the seal...I'm pretty sure I see flaked off paint even on the seal itself... ..Also, did this leak just start or has it been around for a while ???? What I'm getting at is...You did'nt overfill the trans enough to have it come out that vent over the seal did you ??? Just trying to cover all the bases...

If you mean that rounded bit at the base yes it is peeling off.

The leak has been developing after the tranny rebuild. More and more as time as has gone by.

Don't think it has been overfilled, but it spews a liter over the course of a 100 miles on the highway. Possible that the tube was never correct, don't think so though.

It doesn't bang the 1-2 shift when it stops leaking. And will slip in 3rd so I do not think it has been overfilled.

If by chance the TC was painted up past the point where the seal rides and the paint came off in sections I'm guessing that's what took the seal out...So make sure the snout is clean and follow the above suggestions for the install... Anyhow, at this point you have two options...Just replace the seal and take your chances or dig a little deeper and pull the pump to check the bushing... And now for my ....The bushing in question is a must during any good rebuild so I'd hardly think it went bad so quick if you've recently had it gone through...And by the looks of that paint flaking off on the hub and seal I'm betting on the paint flaking off to the point where it made a nice edge to cut the seal making a leak that kept getting worse....