Ralph Nader and all of those safety freaks also got caught staging alot of those "explosions" and so-called problems. A full tank of gas can get nailed by a train and not explode, it's the vapors that blow. The cab mounted tanks are vented! If you feel it's a hazzard, move it. I still can't remember ever hearing of any problems from cab tanks and they've been around for a hundred years.
Good luck with keeping the external tank safe! I've seen more external tank problems due to the fact they corrode and leak and can get hit by road debris or other vehicles. But, each to there own,
Scott