3.08 gear with a 28" to 30" tire would work, or even a 2.73. The 292 should have huge amounts of low rpm torque, so gear low using the 1 to 1 high gear turbo 400. I would shoot for 2400 rpm @ 70 mph, so figure accordingly. If you drive slower, rpm will be less of course. Google rpm calculators, there are tons of them to choose from.
