Toyota Repair: 94 toyota pickup, short circuits, toyota pickup

Question
I have a 94 toyota pickup, 6 cyl 4wd. My odometer and speedometer quit working, my reverse lights work but fail to come on when the vehicle is in reverse, and the light on my dash does not come on to indicate when I am in 4wd.  The speed sensor is not the problem. I'm thinking maybe a power supply leading down to the transmission or maybe a fuse. Any thoughts.

Answer
It sounds like there is a serious wiring problem, there are just too many things that are affected for it to be just a fuse but that would be a godd place to start, check all the fuses with a test light with the key on and replace any that are not good, if some of them blow out again then there is a wiring problem, possibly short circuits etc., none of the items mentioned are on the same  electrical circuit so there are a few things going on that are not related and I would suspect that there may be some wire damage for some reason somewhere in the engine control wire harness.