In general: more fuel+more air in+more air out=more power
If you had a older v-8 upgrading from the 19 lbs. to the 21lbs. would be a good move. But for our v-6s the 19 lbs fuel injectors are beyond efficient. You will need to upgrade with a cam, ported heads, and a 4.2. It is still not necessary unless you want all the hp. for your money.
Something to think about is 1.8 rockers.
$350 4 1.8 rockers $320 4 1.7 rockers
$88 4 the push rods
$80 4 the gaskets
$35 4 the push rod checkers
It all depends on you level of mechanical experience. 1.8s will add 20 hp. 1.7s add 10hp and are compatible with all cams. I am not sure if Bama tunes for 1.8s ,but they do tune for 1.7s.
new engine,1.7 rocker arms,Pipes exhaust, shorty cats , shorty headers,under drive and overdrive pulleys,4.2 upper plenum, throttle body spacer, cold air intake, stage one clutch, shorty shifter, and tune. 8.8 in storage