I used autometer elec fp guage, but really just a 0-100 psi sender and wiring would work, don't even need a gauge. Metco makes a stock rail adapter. Unscrew the shrader valve first though. Then you just run the lead signal wire to the PL. Then in PL make sure it knows its a 0-5v pressure signal. Holley also sells 0-100 psi senders.