I acquired a gold 1963 Avanti about twelve years ago, also in need of total restoration. I am about 99.9% done with it now -- just a few minor details left to square away. Boy has it been a long and arduous journey.
The gold paint the car was wearing was not original, and was darker than the original Avanti gold, which is kind of a champagne gold. I didn't care for it at all. Not only was the paint on my car old and ugly, it was chipping off, and a large amount of bare fiberglass was showing around the radio antenna -- whenever that paint went, it took the previous layers of paint, and the primer with it. I really hope there isn't something in the fiberglass that will migrate to the surface and lift the new coat of paint off one day. Stripping the car (with a razor blade and an air file), I discovered the original color was Avanti gold, but it had been painted white at some point, and then gold again in that incorrect, darker gold color. I took it down to bare fiberglass, which I needed to do anyway to repair a small number of cracks.
All the while I was stripping the paint off, I was seriously torn between Avanti red, and Avanti white. In the end, I decided to go with white, even though I don't generally care for white as an automobile color. But Avanti white is an off-white, sort of an eggshell white, and very close to Ford Wimbledon white. It really has grown on me, and I think the car looks fantastic in that color. Other people seem to agree, since I've been asked by more than one what color that is. I decided on Avanti white in the end because it and black were the only two non-metallic colors Studebaker offered the car in, and black, as others have noted, requires a lot of extra work to make the body perfect, or it will show every wave, ripple, and imperfection in the fiberglass. I decided I wanted a non-metallic color because unlike with metallic paint finishes, you can make invisible spot repairs -- a non-trivial consideration with a car that has that flat, grill-less nose panel, just inviting itself to be chipped by pebbles flung up off the road by the tires of other cars.