Welcome to the world of restoration, Pep! It's complicated and frustrating but very rewarding. I don't know of any reference book at present that can answer your questions, and everyone has an opinion on everything...chuckle. For example...the engine compartment can be different glosses of black depending on the part. The undercarriage could have been different colors of primer, springs could have been coated with cosmoline instead of painted...the list goes on and on. Every car seems to have been different. I can tell you this; if you can find NOS pieces, bite the bullet and pay the price. Repro parts are generally inferior--especially sheetmetal. I deal with Classic Muscle in Winston-Salem, NC. Their prices are very good and the service is good.
My advice for what it's worth is to read everything about restoration you can get your hands on and play it by ear. This site has JohnZ who knows more about the 1st-Gen cars than anyone I"ve ever seen, and he'll shoot you straight.
Good luck and welcome to 1st-Gen madness!!