Reply to "Dash removed"

Clean and tighen the main ground stud and nut that sits right were the steering wheel would be. Look for the bundle of black wires going to a welded stud. That often leads to bad eletrical issues down the road.

Change the light bulbs. Somewhere there is a post about different wattage bulbs that offer a little better lighting.

Check under the windshield rubber. Sometime they leak due to a poor fit. Consider sealing or at a min. inspecting to see if there is a serious rust problem underway.

JackD indicates there is a small screen in the A/C expansion valve that needs cleaning or removal after so many years. Since it is easily accessable now, perhaps a good time to clean. it does mean opening the AC lines which means a vac and recharge is in order.

Tie down and silence the wire harnesses. You might fix a random noise from something banging around.

Clean and inspect the fuse box.

The peddle box has a two coil springs to return and hold the clutch and brake peddles in place. They can fracture over the years. A chore of a job if you are up for the "concourse" approach.

Check the heater coolant hardlines. MAke sure they are sound. Don't want no pinhole leaks in the cab. They are welded in so do not try to tug them out.

Last one; do you still want/trust running all of the current though the old amp meter? Shunt the meter if not done alreay or replace the amp meter with a aftermarket volt meter. Volt meters are a safer option.