What is this and how can I use it?

   / What is this and how can I use it? #11  
Just make a bracket for the fender and mount the valves there.
 
   / What is this and how can I use it? #12  
Your 3pt probably would not work if that QD was separated. The complete assembly could be pressurized if the 3pt lever was engaged.

Should you install a valve, the pressure side of the QD would go in the valve IN port and the other would go to the valve's PB port. A third hose from the OUT port would go to tank.

Check this valve out if you want a two lever small valve.

Surplus Center - 2 SPOOL 8 GPM PRINCE MB21BB5C1 DA VALVE

If you need float, there is another valve available.
 

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