10's on $5,000 ?

Dropping weight on those trucks will be tough.
Bumpers, fiberglass.
Loose inner fenders and tailgate.
Replace the bench with race buckets, the seat is actually has some weight to it.
And a glass hood.
Leave the steel fenders, they are reasonable light.
Remove heat/ac box and carpet/rubber mat.
After all that is out you may have shaved 300lbs.