Can I remove the pump, motor and gear box as a unit to get at the clutch? I removed the 3 bolts and the electrical connection to the motor but it only moves about 3/4 of an inch. Also there is alot of grease around the bottom of the machine and when I moved the gear box, a puddle of oil dripped to the floor (I have the machine on its side). Are some seals also in need of replacement?
You should remove the pump and motor before removing the transmission assembly. Also if you did not remove the agitator, you need to do that to allow the transmission assembly to come out.
With respect to your leaking problem I think you need to replace the transmission seal and top. Here is a link to a really good site that has a good discussion and a good photo and a link to the oil seal kit and a link to the service manual.