Circlip must be in - tap it in with a screwdriver? If not it could wreck your axle and tranny The dust cover sits against the gearbox seal - it's supposed to be firm on the shaft but I've noticed mine are pretty loose too. Maybe some epoxy etc to keep it in place, it's there to stop muck from entering the seal I find it a lot easier to remove the reverse switch and fill from there with the front plug open to show when the tranny is full The reason I switched to 80W-90 was to eliminate a crunchy 2nd gear
