Thanks for your input, Doug- that tank is nice, but looks like it's out of stock until November (seems to be my luck with tanks!!).
I'm guessing a spun aluminum tank wouldn't be allowed to be inside the truck:
https://www.speedwaymotors.com/Spun-Aluminum-Fuel-Tank-11-Gallon-10-x-33-Inch-Offset-Outlet,60364.html?sku=91076257&utm_medium=CSEGoogle&utm_source=CSE&utm_campaign=CSEGOOGLE&gclid=EAIaIQobChMIupHtn9O-6wIVBeiGCh0goQqEEAQYASABEgJaqvD_BwE