'97 7.3L Exhaust Brake Modification
IF THE IMAGE IS TOO SMALL, click it.

Note that, because the BOO circuit is always hot, the mod relays will click even with the key OFF. And they will work with the truck in PARK or NEUTRAL. A disable switch could (should?) be added between the original BOO circuit and the relays.

Owner caption May 2020 · Photo 83 of 196