Underbody Shield problems of the 2004 Jeep Wrangler

Vehicle is a 2004 Jeep Wrangler 4x4 purchased 12/04. Debris accumulated under the skid plate, apparently ignited by exhaust system. I smelled and saw smoke and had a fire extinguisher which I used to put out the fire. Engine wiring harness damaged by the fire, repairs about $2,000. Skid plate design allows debris to come in front of skid plate but not be blown out the back or bottom. I bought the Jeep in part for its offroad capabilities, but am afraid to use it now.