Randy - first of all, congratulations on even thinking that moving the tank out of the cab

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OK - that roll over valve I have is mounted on a stand off piece of piping, 4" if I recall and just because I do have that much room to raise it above any possible gas immersion and plugging. Also, using that reasoning, that's why any new car owner's manual tells you to not 'top off' when filling the gas tank.
You can also put a vent/roll over valve on a piece of gas line tubing as there are two styles offered by 'Tanks, Inc', one being a remote style***.
Now - you being in sometimes sunny CA, how can you afford that amount of gas to fill it at one time. To fill my F350, 30 gallons @$3.60/3.70 gal (yesterday) is over 100 bucks

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Remote Mount Rollover Vent Valve
I'm happy to see it back up, sure hope it lasts.
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