Saturday I filled up my XJ and parked outside over night. Sunday hit the remote start and let'r warm up before I went off to the Library to study. Hopped in and noticed the fuel guage a weebit under the full mark. When I parked it, it was above. I know the sending units aren't the greatest in these things but whats the likelyhood that I was a victim of such a crime? My Jeep is a 96', not sure if it has any anti-syphon junk in it or not. If it doesn't, is there something I can install for a cheap price? Locking gas cap maybe?