Rebuilding a WUR.

[theiceman]

I bought a used wur a few years go for 100 bucks. it sat on my shelf forever.. a couple months ago i put it in my car to test it and the control pessure was WAAAY off... car would barely run .. so i decided to rebuild it .. the reason the pressures were way off is becasue someone " tapped it in" i could see the punch mark on the top .
I want to tap it back out ( i may even turn it into an adjustable down the road.. ) . But for now im not sure how far out in supposed to tap it or what order of magnitude.. is this done in mm ?? can anyone guide me or is it all just trial and error ?

Thanks

[fritzgator]

make it adjustable now. drill it, tap it, put the nuts & washer on and back it out with that set up.