Peter,

After you remove the circlip, you slide the valve out noting position and replace the two O rings. I would suggest the dealer or Miller's in Southern Cal as sources. Hopefully you can get them out without destroying them since they are made of brass. MB made a special for the job. I used to have one. The colored levers can be bought as original equip or a company that advertises in the STAR sells screw on units that require no disassembly. I installed a set years ago, and they worked quite well.Remember to install those valves so they rotate full open and full closed.

Peter

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