10 MPG is low for a SWB 2WD. I was able to get 12-13+ in a 79 1 ton w/ a 12 foot bed. That was with a TQ. I would change out the afb and probably the intake unless a good tune gets you there. Headers make a night and day difference, as those logs are really bad. Have to watch the $$$ though or it is just hot rodding. The carb would be the most bang for the buck I think.