Of course a hot rod 911 does not need to use any of the original paint schemes and colour codes. But if you don't know what you're doing, you're frankly better off not trying to be the Dali of the car world.
The company Glasurit has a neat site with a database of classic car colours. You can search it to your heart's delight. And here you get an overview of the early 911 colours:
Labels: 911, colour, Porsche