Have you considered moving the propane tanks to the underside of the deck? Just spitballing here ... my boss did up a '38 Ford pickup into a flatdeck, maybe I can get some shots of it for you...
Basically to visualize it for you, its the '38 ford cab, and an aluminum flatdeck c/w hydraulic lift.
His is gasoline, but still the same concept - he used some old Labatt's kegs as his new fuel tanks, and has them mounted right behind the cab, basically between the cab and the tool boxes (which contain all the fun goodies for the air ride). Looks pretty good, and lets him have the full deck wide open.
Only other option, if you are wantign to keep them up top, would be to find a custom fab shop to build some aluminum tool boxes/covers for the tanks.
The best rules to form a young man are: to talk little, to hear much, to reflect alone upon what has passed in company, to distrust one's own opinions, and value others that deserve it.
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