Someone correct me if I’m wrong, but did these trucks come with a generic brake controller harness? I know there is a plug under the dash, but did they come with a pigtail with bare wires to splice onto your controller, and then plug into the truck harness? Mine seems to have been lost over the years, and everything I find online is for a specific brake controller. I just need one that I can splice onto my Uhaul special.
There should be a harness located next to your emergency brake under the dash. If you're wanting to install the factory brake controller then that harness is in the dash behind the AC controls.