Sure enough,if ya wanna run a 3:08 rear your gonna have to change out the whole rearend.But that sure makes a lot more sense than getting 7.8 MPG.At that rate I would go broke after a couple of weeks of driving.The only reason I am getting 20 MPG in my 55 with 3:90 gears is the 700R4 overdrive tranny. You can tune that engine and drive very slow,but a 4:57 rear just aint gonna get you good mileage.

http://www.dalesclassics.zoomshare.com/0.html