Have been trying for a long time now to fix the leaks in my transmission. It’s a 1964 727…in a 58 Plymouth. Replaced kickdown shaft seal already now the push button shift cable is leaking at the adjustment dial. Cable itself looks fine but there must be a seal between that adjustment dial and the transmission housing. Any body ever done this? Is it an o-ring? Can it be done without draining fluid? I’ve drained fluid way too many times already. Thanks, Bob