auxiliary fuel tank

Thanks we have had our 07 5.9 DRW Mega Cab Dodge 6 & a half years & have haul rock a couple of times & took a hutch to western Ks for son-in-law as his AC was not working in his truck. So 99.9% of the time I do not haul anything but our fiver. Both of my son-in-laws have trucks so when home if I need to haul any thing I can use one of there trucks, they have used mine over the years. We full time & have a tonneau cover on the bed & it will only be seen when pulling. We got the Meg Cab with a 6.5 bed as it is our truck to pull our fifth wheel, the mega cab so DW can haul grandkids. Don't plan on using the tank when not pulling. Have thought about it a long time & think I will pay for it in two or three years. Also do not like it when my tank gets under half full as I start looking for fuel. As my uncle used to say it is just as easy to keep your tank on top half as bottom half. This way I will have additional 70 gal. on the top half.

Thank for all of the advice
red