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there is a release bearing on the inside of the box
this is a good pic but its a pic with a release lever rather than a hydrolic one they have a pipe that comes out the top of the bell housing down the side of the engine in between the bat tray and end of engine.
1 you place a peice of rubber tube in a little jar with some clean break fluid in
2 make sure the resivour is full to rim
3 open nipple slightly
4 place rubber pipe over the end of the nippleand other end in break fluid,
5 pump clutch slowly until you see no more bubbles in break fluid.
6 nip up nipple
7 pump clutch to check pedel
hope this helps.