I did this back in 2020 and bought them from Speedway. Getting the 3rd LED break light working wasn't very hard, though you do need to tie into your brake light wiring and run a wire up to the cargo light.
I haven't had any problems since installing them, so that is going on 3 years now.
You didn't ask and while very pricey, I have LED headlights too - I basically can see into next week. I did have a problem with one but they replaced it with zero hassle under warranty. I also installed headlight relays too. Even if you don't switch to LED headlights, I say this is almost a must upgrade. But that is of course my opinion.
- United Pacific 110201 Backup Light 1967-1972 GM Truck, RH #92633723
- United Pacific 110200 Backup Light, 1967-1972 GM Truck, LH #92633722
- United Pacific 110213 Tail Light Assembly, 1967-1972 GM Truck #92633697
- United Pacific CPL7172C Park Light Lens,1971-1972 Chevy Truck,LED #92633670
- United Pacific 110127 Third Brake Light,1969-1972 GM Truck,LED #92633724
- United Pacific 90652 LED Flasher W/ Polarity Adapter (need 2 - one for blinkers and the other for hazards)
- Dapper Lighting OE7 with 7" Glass Type upgrade.
Hope that helps.