Lost the lighting on my dash

Sounds like a ground problem when you took the cluster out and when you tightened the mounting screws you got a ground connection back. Redfish mentioned a permanent ground wire. Do that. Over the decades body panels shift, corrosion happens all stuff that compromises the ground path beck to the battery. The instrument cluster gets its ground from the metal in the dash. With the cluster out - no ground - nothing in the cluster works! With a ground wire from a ground point on your circuit board(s) to a known solid ground, like a screw on your steering column clamp, viola! Stuff works!! be careful not to let those alternator gauge connections touch any metal part of the dash.

Remember, all the solid state electronics in the world run on what technicians call "magic smoke" If the smoke escapes, the electronic part is dead. Accidentally shorting a voltage hot part of your cluster to the dash metal will let the smoke out. That has left me with a stupid expression on my face more than once!

ATB

BC