Brake switch

[66Submarine]

The e-brake probably isn't hooked up. The cables rust and seize over time, so you pretty much get one application and you're done if you pull it. If the rest of it is still there you may just be able to buy a new cable and hook everything up. I don't have any trucks with working parking brakes (see above) right now, but IIRC you adjust them under the truck somewhere along the cable; should be fairly straightforward. (Differed a little over the years AFAIK)

Check the taillights and taillight bulbs, and look for "spliced" wires twisted together and taped, or otherwise missing. Also check the turn signal wiring; that's where they split off and become their own independent circuits. If your wiring is hacked it might be hacked there, too.