93 sport lighting problems

I have a 93 explorer sport and just reciently I've been having some electrical problems with the lighting. A few weeks ago both the dash lights and rear tail lights(driving lights) went out at the same time. I checked the fuses and after switchign a few out, noticed that it seems as though this is not the problem. The lights came back on after a few hours on teh road and the problem has been itermittent since then. A few days ago they went back out and haven't gone back on since. THe only thing I can associate it with is a loose connection however I don't want to waste the time opening going though wiring diagrams unless this is really the problem. I'd appreciate any suggestions as to what is suggested since as of right now I can't drive it at night without the tail lights.