[urq] reverse light short

[djdawson2 at aol.com]

My 85 has been back in action for about 7 days... and a strange behavior has started.  My gauges/turn signals etc stopped working when I left work yesterday.  I got home a checked the fuse (#12)... blown.  Replaced, and everything's fine.  I tested the functioning of each item on that circuit, and nothing goes wrong until I activate the reverse light.  Put the car into reverse, and the fuse blows.
 
Any BTDTs?  I have very limited tools where I am, and no place to work... so if anyone has run into this, I'd love to hear a shortcut.  My first thought is to disconnect the reverse light switch at the trans, and see what happens.  I've never seen one of those fail creating a short... but if the entire circuit is disabled, I'm thinking I'll at least avoid blowing the fuse until I can fix it correctly.
 
BTDTs appreciated!
Dave