Headlight switch backlight dimmer blows horn fuse...???

Every time there is a weird electrical problem it is always a 74-76. I pulled my hair out on a couple of these cars. Even installed a used harness from another car . Then the problem switched to something else.

These cars have bulk head and harness plug problems. They must have went to a different vender for the ends. Once you have an issue with one thing . You will be chasing open circuits . These cars have a corrosion problem on the wire ends. Fix one and you cause another by wiggling something you shouldn't have touched. Good luck it could be something simple like slamming the hood real hard.

The only thing that turns me off on a 74-76 A-bodies is the park bench bumpers and the "electrical problems".

Find a complete 73 harness and components front to back. You will never regret it.