Nothing doc said would take more then 5 minutes.
If you don't have an lpr guage and insist on not buying one, try pulling a shim out and chrono. If your velocity drops or becomes inconsistent put that last shim back in. For example my a1 fly loves 57 psi. Put it down to 54 and it gets +-10 over the chrono.
"There he goes. One of God's own prototypes. A high-powered mutant of some kind never even considered for mass production. Too weird to live, and too rare to die." -Hunter S. Thompson