Your chevy truck is coming along great. Always liked the early chevy and with what you had to start with, you've come along way. I'm running 2:76 in my 9" ford rear and get aroung 21 MPG. After I had the heads reworked the engine breath alot better and my mileage went from 16 to 21. Even with the work done on the little 305 that's putting out 303 HP and 313 lbs of torque, Cannot spin the wheels with those high gears Fogure I save on money for tires using those gears, because if I some 3:55 in there, I d probably go thru 2 sets in one summer