Low voltage going to headlight…

It's pretty normal. The headlight switch isn't made to handle the load of the headlights. They all get hot as heck with all the resistance they have. You need to get Rob @crackedback's headlight harness and relay kit. It removes the load completely from the headlight switch and the relays carry the load. The switch is used only as a trigger. Rob's kit puts DIRECT alternator voltage to the headlights and makes them a lot brighter. You won't be disappointed. I have it on my car and love it.