I have basically the same truck and I would just like to say that I am very impressed with your mileage returns.
Just a couple of questions:
What tires are you running?
Do you have manual hubs?
Did the lightweight flywheel make a difference?
Are the road you drive on fairly flat?
What speed do you normally drive at?
I have tried my best and so far I can only get 22mpg out of mine.