Under trailer mounted aux fuel tank?

Could you post a pic of your truck as is now. then we could consider what we see with your statement.
("I have to remove my bed, and will not have room to clear my auxiliary fuel tank.") Some of the offerings
are based on the pic shown, courtesy of trailer dealer.

 

It's actually on a truck out at the farm, but I posted a link I forgot to for the tank in my original post. As it's the in-laws farm I'm unlikely to be out there for a couple weeks.

 

It is immaterial so I will go.

 

Which if it's a standard long bed I'd be extremely shocked if you don't have room to mount a skinny tank. Trailer must have massive front overhang, more than I've seen in any other trailer.

 

Should be plenty of room in front of the trailer for an "L" shaped aux tank.

 

Build a tank in place of the head board ?

 

I doubt anyone on here has experience with this other than reefer fuel tanks. Your idea doesn’t sound bad in theory, but how long is the fuel pump hose going to have to be to reach your trucks tank? Also, you’ll still end up stopping to refill the trucks tank, granted it’s quicker than fueling at a truck stop.

IMHO it’s going to be better overall to keep the fuel on the truck and find a way to have the trailer custom made so you have the clearance for one of the “L” shaped tanks.