Banjo5

I forgot to mention that the relay and majority of wiring was done down at the junction box down by the emergency brake, where the cargo light wire was picked up and the marker light wire came in from the under hood fuse box.

I had a similar issue with the rear facing flood lights, however my cargo light goes off when I put the truck in reverse. I didn’t like the idea of the rear facing flood lights coming on when I unlocked the doors at night as well, kinda blinds me when opening the door. I made the following modification: got a 12 Vdc relay with com- NO ( normally open) and NC ( normally closed) contacts). I wired the hot wire for the cargo lights to the NC contact, then wired the marker light hot wire to the NO contact. Then connected the wire to the rear facing flood lamps, to the common (com) contact. I added a SPST switch near my steering column ( you could put it anywhere that you like.) I picked up the hot wire from the marker light circuit, ran that to the switch, then the other side of the switch down to the relay coil. Negative side of the relay coil to ground. this all works the following way: cargo light switch in the cab normally operates the rear facing floods, switch on dash operates the rear facing floods any time the switch is turned on when the marker lights are on (have power) this way I can use them when in reverse, any time I choose, and no blinding me when entering the truck at night.