gauge circuit board

This left board connection is too close to the top of the panel. Service manual states to pull the panel outward and tilt face down to disconnect. Figure in the age and stiffness of wire, not quite enough wire provided. Too often the upper pins are bent/loosened or leave with the harness connector.
A new board will be pretty much identical to OEM. It does have slightly shorter pins and they are soldered to the copper trace. If they ever do lift away from the board they will peel the trace away with them.
To fix what you have and improve serviceability...
Buy a basic 4 wire trailer harness connection, available most anywhere. Solder 3 wires of this male connector at all 3 of these contact points. Maybe use the 4th wire with a ring terminal under a screw as both a chassis ground and a anchor for this soldered on "pig tail". Replace the factories female harness connector ( with broken pins in it ) with the female side of trailer harness connector. I route my inst' panel ground wire to a added screw behind left kick panel. Routing it to a column support bolt works but... it'll get disconnected when the column is lowered during panel service. So it doesn't help with panel testing before everything is bolted back together.
About new paint... Most everything electrical on these older vehicles requires a metal to metal contact for chassis ground path. So there are a lot of places where we must scratch away small spots of new paint. Front park turn fixtures are plastic so they do have a ground wire routed to radiator support ( same with headlights ). Rear brake turn fixtures are grounded through their mounting hardware. A ground jumper from firewall to engine block is a player in this ground path. At some year model the factory added a ground jumper from radiator support to the neg' battery post. This is a good addition for front lighting, etc..
Some of the aftermarket ( ebay ) signal switches are junk so check that you do have power out of it first. If it is working... check fixture grounds.