I'm in full agreement with Richard on the books he's recommended, although I'll never give Tex Smith another dime in my life (any of you that were subscribers to Hot Rod Mechanix might understand). Read and reread till you fully understand the process. And if the truck is valuable to you, do as Streets did, find some old junk cabs and do some practicing. That way you prepare yourself for what to expect, and can see just how much extra work is necessary to re-align the top and bottom.

Chopping is about more than just taking out some chunks of material and lowering the lid. It's all about proportion. It gets lost today with the mini-fad of "old time" cars (rat rods, nostalgia cars, whatever). Some people seem to go to the "more is better" school of design. That's great if you're doing a '58 Buick and you love chrome. It's probably fine if the reason you're building the car is to make a cartoon statement, meaning all characteristics are exaggerated. But if you want to improve the lines of the vehicle, and have it remain functional, then you need to experiment for what looks good. The way we used to do it was to take photos of a rig and then chop the photo, figure the scale, and that way know how much to take out, and what kind of reshaping need to be done so it "flowed" nicely. Today, tech oriented folks can use software to do that. Whichever you're comfortable with, you should do the design first.

Now to counter my buddy Streets (one of my favorite things! ). One of the nicest chops, and most effective style wise, I've ever seen was a '53-'55 F100 that was cut 1 5/8 inches. No longer did the cab heighth look awkward. It looked like the factory styled it right for proportion. And to me, that's the proof of a good chop, when it almost DOESN'T look like it was chopped.