Have you regeared to accommodate 37s and driving at higher elevation?Please keep us posted. This is what I'm planning to do as well. Currently stock motor, 6 speed, 37s. Great MPGs in town (18-19MPG), poor on the highway (80+mph, 15-16.5MPG) because 6th is so high. It takes a lot of work to drive it on the highway, especially for me going between 5200 to 7300 ft of elevation on my commute. I worry about the stock clutch handing a power adder.