727 transmission leak

Mine was leaking also, I first thought it was the pan. Bought a new stamped pan sealed up really good, still leaked but turned out to be the shift shaft seal. With the 2 1/2 in TTI pipes and bad fingers ( arthritis ) I couldn't get in there to change it so I took it to a buddies transmission shop and had him change it. Best $50.00 I ever spent. But I still have a leak and it seeping from the front coolant line . I have replaced the brass fitting a couple of times and replaced the line it's self but still can't get it to stop seeping. Last time I changed the fitting I used Loctite sealant 567 on the threads and she still seeping. I was thinking about trying Ultra Black gasket sealer next. Unless someone has a better way to seal it might have to take it back to the tranny shop.