727 leak

Best I can tell you is to degrease the trans, drive it, then investigate. Shifter/kickdown shaft area ( could be seals or worn shafts) the front pump and seal, the dipstick, the extension housing, the reverse shifter shaft, pan and/or gasket. Or case porosity. I believe the FSM covers possible leaks, and heres maybe not the best article but it covers leaks. https://www.allpar.com/mopar/transmissions/torqueflite-fixes.html