hello, i have the power plenum as well, but I am trying to find what size washers are needed to get it to seal correctly....I tried the dowty washers that came with the gun's seal kit, but there are 2 kinds - one thin one that was already on the gun's reg gauge and a thicker one. Neither seems to seal this plenum well. What did you use to mcgyver this thing to seal?I only had a couple of issues..
1. Had to shim the dowty washer to get the plenum body horizontal.
2. You have to purchase a new gauge. The plenum requires 1/8 bspp threads 25mm diameter