904 Tranny question

I am restoring a 68 dart with a 170 cu. in. slant six with a 904 tranny. The car runs fine as long as it has tranny fluid however, alot of tranny fluid leaks out. When the car is level and warm and in neutral, I see a drip from the front of the bellhousing and I also see drops hanging from underneath where the speedo cable goes and the tranny pan. Very fresh fluid. Any help would be appreciated. I hope I don't have to rebuild it. It shifts fine and runs fine, but the thing leaks like a stuck pig. Please help. Thanks, John.