Dumb question for all you guys. In the 70's there were LNG and propane conversions done all over the place. The Los Angeles times ran every one of their newspaper delivery trucks on one of those but can't remember which one. It must have been safe because one of their trucks came in for repair having had the pressurized tank knocked completely off the truck. Nothing blew up. A few indivuduals converted cars and even small Toyota trucks placing a small tank accross the bed up near the cab where a tool box would go. My question is, what the heck happened to that technology and why was it abandoned?