I like this one... has some extra gallons for longer distance before fillups...
68 gallons times 15 miles per = a little over 1000 miles
http://www.tank-depot.com/Drawings/Ace/SP0050-RT.pdf
IMHO, and the truth be known, none of the mods we do for our trucks are DOT sanctioned/approved/Appropriate tax paid and so-on
Not that I haven't tried...No one knows what to do at the local DOT. But thats a whole nuther can of WORMS-mad
So with that said, I like the tank above, its below the bed line, the bed is right at 19 inches, which it two inches above the tank, (gives room for the top described below).
Its about 42 inches wide, that gives you room on the side to put a filter and some plumbing...
But, its too deep for a short bed and just about too deep for a long bed, that is if you want to put it all on one side. (it will bump the wheel wells)
If you put it in the middle you are good to go...
I like it so that you have enough room to put a 1 inch sheet of foam insulation on the bottom, sides, ends and top.
For the "lid" which would cover the tank from one side of the bed to the other and from front to back, I would have a HVAC metal person make me a top that has ears similar to the way a tool box would rest on the bed. It also looks from the road very similar to a tool box.
This makes for a GREAT cover to keep the elements out, OH did I mention that it make for a good stealth setup too?
I have a 100 gallon Contico metal tank now, but not for long... the WVO polermerizes (sp?)
on the sides and makes for short life on the filters... one every 100 gallons... Plastic is the way to go, cheap and good enuf... Aluminum may be the way to go, but $$$...no have...
Boy houdy, did I do a long one or what????
Good luck all, and don't forget to PURGE !!!!
RoReRi