Another member just had this exact problem, it ended up being the "starter enable switch". Here you go....
http://www.s197forum.com/forum/showthread.php?t=77898&page=2
Yeah, that was the first thing i started checking after it wouldnt crank. I jump the NSS, anf the cruise cut off switch and no luck with me. The statewr relay had 12v key-on power and also 12 start pos so its clearly a groung fault somewhere! Where?, I dont know yet lol. so for giggles, We jumped a ground wire to the neg (on starter relay prong) and it fired off. Problem is there is no wire that goes under the realy where i jumped the neg to so im puzzled to whats going on but it doesnt seem to interfere with anything else the way it is so i may leave well enough alone???