my turn signals flash very dim and i don't have any park lights. it looks like the turn signal housing grounds the bulb. if i hold a wire onto the gold part of the socket, it will flash bright. how do those sockets stay grounded?

next any known issues with the park lights not working?

Grounds- rusted or coroded-clean them and retest-or can run a new seperate gtound wire fron base to body areas & be sure the body,engine, frame is grounded good-just usually a corosion problem

also - check the wiring conection from turnsignal switch areas- and always get a "heavy duty" Flasher from autoparts.

clean all the grounds. For lights, this means the housing where it touches the body, the body and the screws that hold them together.
If you have the time, one of the best things to do on an old car is to spend a few hours or a full afternoon going through and cleaning any and all electrical connections and grounds. This includes all the fuses, an connection, and anywhere ther is a ground, including the battery negative cable, Alt mounting, ground wires to the frame, motor, body and doghouse. Also whereever there is power supplied and the item (like lights) grounds through the component.

We just ran into the same issues with the tail lights on Randys truck ,, the socket can have enough corrosion between it and the housing to do what you are saying ,also the wires sometimes will be broken inside the insulation where ithey go thru to the socket. Check for power at the connectors and if you are good there it will be isolated to the tail light housings themselves more than likely.

When the time comes I am going to remove all the wiring and go with one of the aftermarket wiring kits. The wiring is pretty simple in these old vans and shouldn't take too long to do. I have wired a couple of airplanes and one thing I did on them was have a ground buss that all the ground wires ran to. Don

A ground buss is a good idea for a 'glass bodied car, but overkill for a steel car.
This stuff works for 10-20 years pretty well. It's when they get older and the bare metal corrodes that these issues start.

Solder a ground wire onto the lampholder - screw it to the body...worked well for me.

i got the left front to work by drilling a hole in the bulb socket and pop riveting and eyelet to a wire that grounds on the body with a self tapper screw. did the same on the other side (r/f) no change. the park lights do come on at the first click. i never knew. thanks. still baffled on the right side.

Just an FYI:

A multimeter may show voltage, but a test light will confirm that you have good connections.

My turn signals were screwy. I had voltage, but no flashing turn signals. Turned out the spade clip connections to the fuse block were 'slightly' corroded.