Looking for more HP and better fuel efficiency on 1992 Chevy C1500 5.7?

It already has a few mods to it. Spectre Air intake, Duel flow-masters exhaust, recently did tune-up on 6/01/11. will a throttle body spacer help out the HP? and new fuel line and pump help out with the fuel efficiency? Please give me suggestions on what to do? she sits at 179k for 19yrs.