It's that way in '94, too. 

I don't have a diagram or know the colors, but you can get the wires at the turn signal controller, or at the back of the frame.  It wasn't that hard ti figure out with a test light.

I changed the wiring at that turn signal control, and made the trailer turn signal wires turn/stop signals instead....that makes all the lights on the back of the semi trailer come on as brake lights instead of the turn lights staying dark.  If you don't want to do that, you could run the gooseneck wire harnesss seperate from the big trailer harness.