1995 Chevy Silverado Won't start

My truck will not start and I can't figure out why. When I turn the key, all of the dash panel lights up, radio works, but the engine doesn't crank at all. The battery, alternator, and starter all seem good. It has been suggested that it is a wire/ fuse/ fusable link, but the fuses check out and none of the wires attached to these components seem to be bad, although it is very hard to trace them.

Any suggestions?