I've played around with the idea of buying a new stock tank off ebay, they're under a hundred bucks, and sectioning it. By adding another 2 " of height in the middle, it would increase the capacity a couple gallons. Not much, but I've already got a 5 gal jerry can on my swing away so just a couple gals more in the tank would be cool. If you already have a body lift and didn't raise your tank too ( I did so not much room left ) you should be able to squeeze another couple inches upwards. I'd only do this to a new tank that's never had gas in it, but I really think it would work.