Parking light wiring problem with a '54 grill

[Hogger54]

I've got a strange issue with the drivers side parking light. Hopefully I explain this well enough.
No wiring kit, I'm doing my own.

So, I have isolated the power so that the only thing hot, is the parking light wire on the front of my truck. Power comes from Batt, through ammeter. Then other post on ammeter goes to alternator, and to my acc. switch. Then from acc. switch to headlight switch. headlight switch to fuse panel, then out to parking lights.
I have isolated left side and right side, and the problem still exists. Passenger side light works fine.

Here's the problem. My grill doesn't sit quite flush with the fender, about 3/4" out on the bottom corner. This is with the grill screwed and bolted in most positions except the bottom drivers side corner where the parking light is(a few screws removed).
With the bulb in the socket, the light works fine, but when I push the grill back in place against the fender, the light goes out. I'm pushing it back about 3/4 of an inch. Take the pressure off the grill, and the light comes back on. So, it must be grounding out on the fender right?? No, because the grill is already bolted and screwed to both fenders, and the radiator support.
Now when I use my voltmeter with positive to the parking light wire, and negative to the fender, it shows 12V. Push the grill against the fender(just like when the light goes out) it still shows 12V. And when I move the negative line to the hole in the grill for the parking light screw, it shows 12V. Push the grill against the fender and it drops down to about 0.

I'm using all new wires, new terminal strips, and new bulb sockets. I've tried a different type of guts in the socket, and it still does it.
I'm so confused. Any ideas??