I had a 73 3/4 ton 2 wd, extended cab, long box, camper special, 440,(originally a 400) 727, 4:10 gears. It was a brute, 5/8" wheel studs, big suspension stuff, front & rear sway bars, over load springs. 7 mpg empty or loaded, driving @ 55 or 70, with or without the wood topper, pulling a trailer or not, didn't matter, 7 mpg. Did drag that car trailer through the mountains in PA pretty easy though, except that 6%, 6 mile uphill grade while I had a 60 300F on the trailer and a box full of parts. That one made it work and lead to its death a few months later. Sorry, no pictures. Gene