Clones and restamps

[bbg]

I follow the information you folks post regularly as I am always trying to learn more from those of you who have been in the hobby for a long time. I see more and more posts regarding clone cars and restamping. How can you tell if a part has been restamped? I have heard that there is some sort of dye or something you can put on block stampings. Is this true and what is it? How about the aluminum surfaces such as the alternator or distributor? Isn't there someone who is supposed to be going through the GM archives? Will it be possible to submit a vin # to them and get a detailed break down on a car? If so will this info help people to properly restore their cars, and document what they were originally built as? Want this make the faking and cloning nearly impossible to do? Sorry for all the questions, just seems like there is a lot of monkey business going on out there. It makes an uneducated fellow like me apprehensive to buy anything.