I have rode three tanks of gas, from that I got an average of 36 mpg. That is eight gallons per mile less befor my stage 1 up grade. I would like to get more mpg. I have a 2008 FXSTB with SE heavy breather, SE slip on mufflers, and Gen 3 (with factor settings). Average crusing speed is 65-70 mph, mostley highway riding, and I'm not heavy on the throttle. What changes should I make to the Gen 3?