It’s an easy but time consuming swap. I did it many years ago on my 81 GMC.
The original power door lock setup on the early trucks used a 5 wire switch. It was much more difficult to wire and troubleshoot if problems occurred. It’s difficult to explain how exactly the circuit works, but basically pushing one door lock button used the opposite switch to complete a circuit. Lots more connections, lots more contact points, lots more potential for failure points. There is no way I would every consider using the 5 wire setup!!
My solution: I used a door lock relay found in most 90s to early 2000s GM vehicles. The switches only use 3 wire (orange: power, light blue: lock, white, unlock) the blue/white wires are triggers for the relay, which simply switches the polarity to each door lock acuator.
I used actuators from a later truck, they are much smaller, don’t require nearly the current to operate, and a very common to GM vehicles. Your local salvage yard probably has 50 cars that used them. The actuators are common, the mounting brackets are unique to the vehicle.
