Amanda, here at Copy-Pro, just called her dad about his Ranger, 4-cyl, IL, dual -sparkplug-engined, manual transmission Ranger of the same era.
He recorded around 20-mpg in town, and 25-30-mpg on the open road,naked, without any mods at all.
I believe that Ford Motor Company published Cd 0.40 for this generation truck.
The Chevy/ GMC , S- 10/ Somoma was Cd 0.42.
The original ISUZU,Chevy, GMC S-10/ S-15 was Cd 0.475, which Gale Banks was able to get down to Cd 0.315 for their 'Syclone on the salt,' land speed record at Bonneville in 1989.
I suspect that 'hypermiling' did play a role in the 67-mpg claim, but at it's frontal area, I wouldn't be surprised if she was knocking off mid- thirties at real highway speeds.
