Headlight Switch Overload

[1985GMC]

85 gmc k2500. single headlights

the taillamp feed and battery fused are the two orange wires the crimp together then get place into headlight switch. when i turn the switch on, every light works except the headlights. my multimeter is telling me OL overload on that terminal.

i actually had this same issue two years ago and got lucky and the headlights randomly worked again.

Why is the switch overloading at the taillamp/batt fused spot?

do i have them incorrectly crimped together?

thanks