Attention: TDR Forum Junkies 
It appears I dropped the ball, for some of you, in failing to enclose instructions with every gauge that I sent out. I've been deluged with emails asking for directions.
To that end, here are directions for hooking it up and using it:
If you have a 98. 5 through 99 model truck, you will need to remove the threaded plugs in the test ports on top of the fuel filter housing, and install the two Schraeder-type valves I included with your gauge. Be careful not to over-tighten the fittings. The gauge hose can then be connected to either fitting for pressure readings. Finger-tight only! Do not use pliers to tighten the hose connection!
For the 2000 through 2002 trucks, there are two Schraeder valves already installed on your fuel system. The most important one is on the VP44 injection pump, the other is behind and under your fuel filter housing.
To located the valve on the VP44, stand at the driver's side fender, let your eyes run from the top of the battery over to the engine. The black plastic semi-round cover you see is the throttle housing. Look directly below that housing, you'll see the VP44 pump. There are two brass colored fuel lines running to the side of the pump that faces you. The fitting on the right has a black plastic dust cap on it. Remove the cap, there's your valve. Connect the hose end to that valve, finger-tight only, and run the hose straight back to the windshield. Tape the gauge to the windshield (3M box sealing tape works fine, leaves no mess) as high as it'll go (so you can read it from the driver's seat), allowing enough slack to close the hood. Don't worry about pinching the hose, it'll be okay. No bleeding of air from the hose is necessary.
Start it up, and check for leaks. Shut the hood, and observe your pressure at idle. Go for a drive, observe your readings at cruising, light throttle. And then observe your readings at wide open throttle. Idle should not be below 11 or 12, cruising should not be below 10. WOT, it should not drop below 7 or 8. If it goes to 0 psi at WOT, the lift pump is dead.
To that end, here are directions for hooking it up and using it:
If you have a 98. 5 through 99 model truck, you will need to remove the threaded plugs in the test ports on top of the fuel filter housing, and install the two Schraeder-type valves I included with your gauge. Be careful not to over-tighten the fittings. The gauge hose can then be connected to either fitting for pressure readings. Finger-tight only! Do not use pliers to tighten the hose connection!
For the 2000 through 2002 trucks, there are two Schraeder valves already installed on your fuel system. The most important one is on the VP44 injection pump, the other is behind and under your fuel filter housing.
To located the valve on the VP44, stand at the driver's side fender, let your eyes run from the top of the battery over to the engine. The black plastic semi-round cover you see is the throttle housing. Look directly below that housing, you'll see the VP44 pump. There are two brass colored fuel lines running to the side of the pump that faces you. The fitting on the right has a black plastic dust cap on it. Remove the cap, there's your valve. Connect the hose end to that valve, finger-tight only, and run the hose straight back to the windshield. Tape the gauge to the windshield (3M box sealing tape works fine, leaves no mess) as high as it'll go (so you can read it from the driver's seat), allowing enough slack to close the hood. Don't worry about pinching the hose, it'll be okay. No bleeding of air from the hose is necessary.
Start it up, and check for leaks. Shut the hood, and observe your pressure at idle. Go for a drive, observe your readings at cruising, light throttle. And then observe your readings at wide open throttle. Idle should not be below 11 or 12, cruising should not be below 10. WOT, it should not drop below 7 or 8. If it goes to 0 psi at WOT, the lift pump is dead.
) finally got to hook up today. I'm real happy I got the gauge but not happy with the results, correction: glad I checked before the becoming a member of the big VP44 $$$$$ club. So here goes the readings; pre filter @ idle 6. 5#
, post filter @ idle 6#, (proves there's a good clean filter in there-I installed less than 3000 miles ago) @ a moderate cruise 50 mph w/marginal throttle 5#, WOT "0#' 
. Time to have fun fun fun with the dealer:-{} I'll research the shop manual first. 
