Dash lights,Tail lights

88 s10 dash lights, tail lights do not work. As soon as I turn on the head light switch the fuse blows. Is there a process of elimanation I can use to figure out what is bad? Are these the only lights that work off of this fuse?

I figured it out. The radio is bad, or the wiring to the radio. When I removed it the fuse stoped blowing and lights work.