chemical strippers are nasty, and they don't save you a lot of time on big surfaces. if you have a part that has 5 coats of apint on it, resort to the chemical stripper, else, stick with the 80 grit for large-scale bulk paint removal. DO NOT USE chemcial strippers on the top, it will melt the plastic it's made of.

after you get the big paint off, move to 120 grit, then to 220 grit. after 220 grit, coat the whole truck with a self-etching primer. then WET sand the whole thing with 400 grit. the water will keep the paper from clogging, and will show any high spots in the paint. after you get it where your'e happy with it, give it another shot of self-etch primer in a different color. go over it again with 400 grit paper, use a good long sanding board so that you can see the high and low spots when you go through them. you'll have to lather/rinse/repeat a few times to get the truck where you want it before you finally paint.

painting a truck takes about 40 hours of good hard back-breaking labor. actually putting the paint on the truck takes about 2 hours. it's kind of like having a wood floor installed. coating the floor with polyeurethane only takes afew hours, but it took a real long time to get the wood underneath it.