Blowing fuse when turning on headlights

I have a '73 CJ-5 and just recently replaced my wiring harness with a painless fuse block system. All is grand untill I switch on my headlights. I bought a factory replacement switch do to the lack of any switch. I can pull on the parking lights and won't pop the fuse but as soon as I pull on the head lights it pops the fuse. Now if I turn off the key and pull the switch then turn the key on all is fine. Do I you think I have a bad ground or a bad switch? Any help is appreciated.

P.S. the wiring was so hacked on its all new. front to back.

 

I had the same symptom on my '99 when I switched to LED rear lights. Two of the rear wires were touching and it shorted when the headlights (and thus clearance light rear) came on. Popped the fuse.

 

Yep, you gots a short someplace.

 

Hmmm; Don't turn on your headlights when it is extremely dark. Pulls way too much current on your headlights.

 

I'd recheck your wiring.
the switch has a circuit breaker built into it, so I would reason from the switch to the lamps is okay.
Look at connections on the switch and/or make sure there isn't a wire pinched under the fuse block.

 

Did you reuse all the old lights? You got a short somewhere. When I rewired mine, the license plate light was shorting out on the bumper and popping the fuse. I think its at one of your lights somewhere.