Tail lights and courtesy light Quit!

[GTXracer]

 My '86 Chevy Silverado Suburban has a lighting problem. We recently changed the turn signal switch and everything worked fine. Now the tail lights and the courtesy light under the dash don't work not too mention the fuse burns out. The overhead interior lights work. Of course the instrument panel lights won't work as well. We spent the past weekend trying to sort out the problem to no avail. Any and all help would be appreciated. :-( 

[Captkaos]

You have something hot grounding in the harness?  Aftermarket radio?  Any modifications to the under dash wiring recently?

[GTXracer]

 Thanks CaptKaos. We changed the turn signal switch recently so you could be right considering the difficulty we had getting the harness down the steering column. I did have a new stereo system installed a few months ago but everything worked fine after that. Isn't the courtesy light under the dash on the same circuit as the dome lights? I also bought another new turn signal switch in the event something is awry and a light switch. I hate electrical problems.
As an afterthought, is there a link for wiring diagrams on this site that will allow me to print out what I need?

[bd]

Courtesy light shares the tail lamp fuse.  Dome light is separately fused with horn.

1986 Wiring Manual

and

1986 Service Manual