I recently purchased a 63 4000 select o speed tractor. It runs great, but there is no response from the transmission. I received my service manual today and removed the top cover to view the controls. I can see no fluid flowing any where, and there are no moving parts. I made sure the pinion was disconnected and cycled it thru the gears there was no change. I also removed a test plus and found it dry. The trans fluid is clean and full. I am thinking the torque limiter clutch is out. Anyone have any insight or advice? Is there a inspection cover somewhere i missed to verify this?