Ok,
To my knowledge they never used a clutch safety switch until like the 1995 model year (when ODB-II was introduced).
So, this leaves us with the possibility of a mechanical problem... Maybe the clutch isn't disengauging properly and causing the motor not to start (for obvious reasons)...
Try starting it with the clutch pedal pushed in, transmisison in 1st, and with your Foot off the brake. WARNING: Do this where there is space around the Jeep incase it decides to lurch or move. If it tries to move, you then know that the clutch isn't disengaging properly.
-Nick

__________________
1988 Jeep Cherokee w/ 410,000+ miles. Now a
100% Electric Vehicle!
NO Gas, NO Emissions, NO Problem! --
http://www.DriveEV.com/