Ok thanks for that. I need around 30 gallons I think and can't get that between the chassis rails. I could get some, maybe 5 gallons in each tank between the rails and the driveshaft. And the remaining 20 gallons above the chassis rails against the front of the bed in a single custom tank, kind of "n" shaped. but then no room for the exhaust unless I run it outside of chassis rails and that gives me issues of clearance between cab step and frame and rear tyre and exhaust and frame. So probably easiest to just run it in the front of the bed as central as possible. Just like frank ZXs F100.