You have basically two choices if you're trying to duplicate a manufacturers finish: Buy spray equipment, which is expensive by the time you've collected everthing you need, or go with the aerosol spray cans from Guitar Re-ranch.
Before anyone scoffs at the spray can method, you can get some surprisingly good results with the Re-ranch stuff - especially with solid colors. I did my first guitar build in Lake Placid Blue from Re-ranch. The LPB is a metallic paint, so a little extra care is needed over the standard non metallic solid colors. It's not that big of a deal, you just have to avoid sanding the color as much as possible, instead sanding and polishing the clear top coats to get the desired finish.
I've yet to find a comprehensive color formula chart for mixing any of the old Fender and Gibson colors. Stew-Mac's book on refinishing has a few, but many more are missing than included. The old Dupont automotive paint formulas don't translate directly to the lacquer tints available today. Those companies and custom builders who have re-created these formulas, aren't sharing their information either from what I've seen.
So if you wan't to shoot the colors using your own spray equipment, you're left with experimenting with different color tints until you find the right formula. For instance: Create an opaque white lacquer and add blue (dark) lacquer tint a drop at a time until you get close to a Daphne Blue color. Then you paint a sample, let it dry, and then compare it to a sample of the original color. If it dries lighter than it went on wet, you start over, this time adding a little more tint. Sounds like fun, eh? It isn't. It's time consuming and hit or miss. But, if you happen to hit on a color, you can duplicate it over and over...if you remembered to write the formula down as you were mixing.
I've used the Preval sprayers as well. You can pick those up from Home Depot, Lowes, Ace, and the like. I don't really care for them for body painting, but they can work ok for spraying on neck amber or even clear lacquer on a neck.
I've seen a few Krylon jobs that came out pretty good too, but Krylon doesn't have any of the classic colors.
