on the fuel rail behind the alternator there is a schrader valve. as long as the key is off the pump wont come on. So use a screwdriver and bleed down the pressure. then change the regulator and install the gauge.
no problem... you will find that if you remove the upper intake and take the 2 screws out that hold the fuel rail to the intake that it will bealot easier to remove the fpr.
yea what he said, trip the inertia switch in the trunk with a screwdriver while the car is running... it will shut off in about 5 seconds, and u will have 0 psi and no mess from draining the schader valve
only odd thing...when i did that to my 5.0 while it was running...sob kept running...barely but it kept running and i was like wtf!??! all the others i have done it to died out no problem.