As it is a off road truck, spending big money to paint it is a waste. Spraying paint is like anything else, the more you spray the better you get. Primers and sealers and top coats are all different to spray. The time of day and temperature of the day make a difference. Every day is different, you may spray good today and crappy tommorrow. Heck, if you want practice, spray your house, its the same thing.
If you haven't priced paint and materials yet, you should get to it. It will really shock you! The new paints are all very costly. A good paint system ( base primer, fill primer, sealer, base coat color, clear) to do a whole truck will be $500 to $700 + depending what you choose. Thats not including paper, tape, sandpaper, putty, files, blocks, thinners, clean up thinner, cups, masks, paint suits, etc.......
Go with a fill primer and enamel top coat with lots of hardner. The hardner dries quicker so its easyer for beginers to spray. In 6 months from now it won't matter what you did or did not due. It will be scratched and dented anyway.
