i feel your pain, i rebuilt my 1st 727 2 yrs back and had a main seal leak from day one and i havent even driven the car yet (still a running project) but it got so bad a few weeks ago that i decided to pull the tran and replace the seal. i did skimp and use some cheap parts when i reb uilt it, so i went to carquest and got a good seal and now it doesnt leak one drop.