Original V3 units on the road have a design flaw that allows the pressure switch to take the bullet for an electromagnetic pulse generated during pump shut-down.
This retro-fit solves this problem by placing a quenching diode over the stock diesel pump. As your pressure switch has been most likely weakened by constant power spikes shunted through it, this solution includes a new pressure 55psi switch (3 wire), a quenching diode, and additional T-taps if attaching to a 6.0 Powerstroke fuel pump. (7.3 owners need only use the default ring terminals).
Installation of this diode is straight-forward. Simply place the RED WIRE on the + terminal of your stock diesel pump, and the BLACK WIRE on the - terminal of your stock diesel pump.
(This solution replaces the previously used RELAY RETROFIT for pressure switch protection).