Oh another thing, after looking at your pictures again your dash bar is rusted to shit and might be having trouble grounding.
I'd take it out and sand that rust off of it.
Spray it down wioth some paint and primer and then clean the grounding points again just to protect it and make sure it has solid contact to the chassis.
Not only will it look nice but it will protect it for the future and might be another source of your grounding problems.
Couldn't hurt right?
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