yhe yoke has a plug in the end with a small hole ot let greese push out if it gets closed up a lot...it can blow that plug out also.
spay it down good with carb cleaner and use air hose to dry,then throw hand fulls of baby powder around suspect area of leaks.
this will slow it down and show right were its at.
check the low/revs lever pivot,you can see it at the back of trans just above the pan rail,the tail shaft has a nub that holds it from sliding out,the o-ring will leak and is ofter over looked when its leaking.
check the shift selector seal after cleaning with baby powder also
I would look at the oil send first thing to rule it out,could also be the end rails on the vally pan.
the rear seal retainers can/are a pain to seal up some times,use a good seal like one roadhazzed sells to get a good one,check the ends of retainer also to make sure they are in shape and line up.
good luck