Axe the seats,carpet, carpet pad, door panels, sound blocker, speakers, radio, glove compartment(lifts out), ash tray, overhead console(if you have one), jack, jack tools, dash bezel, those things can be removed and replaced in an afternoon. If you get serious you could also remove the headliner and sun visors(they're not bad).
Also remove any excess coolant, yank the washer fluid bottle, windshield wipers, wiper motors, yank the fuel tank and mount a 5-10 gallon fuel cell in your toolbox, pull the rear bumper, the cable box for the spare tire(4 bolts hold it to a sub-frame under the truck). Also you could pull the plastic wheel-well liners, the heater box, AC compressor, lines, condenser(sp?), ect...
There's still more but I think that you get the idea. Now most of this is getting extreme, but thats where it looks like you're headed.
I've got some other neat tricks

. If you want some more ideas just PM me.
Later,
Wes