Riffman-
The Illinois Vehicle Code has a few statutes that cover these things. Check with your local police dept., who should be able to make copies of the statutes for you, if not, let me know, and I can fax them to you. In the mean time, I'll give you a brief summary of them.
12-607: "...unlawful to operate a vehicle upon any highway when the suspension system has been modified from the original manufactured design by lifting the body from the chassis in excess of 3" or to cause the horizontal line from the front to rear bumper to vary over 3" in height when measured from a level surface".
12-607.1: "...first division veh can not have frame to ground clearance in excess of 22"...lowest portion of body floor shall not be more than 4" above the top of the frame".
12-608: "...unlawful to operate first div veh with front and rear bumper heights in excess of 22" measured from a level surface to the highest point of the bottom of the bumper when veh is unloaded and tires properly inflated".
If you should decide to go ahead with the mods, and they are in violation, they are Class C Misdemeanors (most minor violation) and punishable by fines not less than $500, and the officer making an arrest for these violations has to order you to remove vehicle from highway.
I don't think a lot of officers would mess with you about it (speaking only of experience in the chicago area), but there is always that one that thinks he can save the world. Hope I didn't rain on your parade...
