Extra fuel capacity for towing

I'm researching my next truck, and CC LB ED seems like a good fit. . One drawback is the fuel capacity which I think is ridiculous; I feel that way about all Ram diesels, since the HD line also lost capacity, especially considering Ford has the DEF tank in the same place, but you can get up to 33% more capacity, even with the gassers.


I will be towing an RV or boat at some point. 10% did a mod with a 20 gallon RDS tank, but I have a 90 gallon RDS tank/box combo I picked up on the cheap that was going to be used in my 08 3500. It's 20" wide, the 20 gallon is 14"; how much room is between the front of the box and the tubs on the LONGER boxes? I'm hoping to use what I have, as this was an expensive tank when new.


On a separate note, has anyone relocated the vent on the stock tank? I did the mod on my 08 and, with the larger sized vent hose included with the kit, managed to squeeze in another 9 gallons. Since no-one makes an aftermarket under bed tank for the 1500, this would be almost as good for way cheaper.