No, not all of them came with an overflow tank. If you've got 3 donor cars with overflow reservoirs, you are ahead of the game my friend. Use one of them. Are they stock, or aftermarket? Clik this link; it's the overflow I've got mounted in my car FOR NOW until I can get the proper one. If this is what you've got, they are common and easy to replace at small $$. Please post a picture of the spares you've got. If they are original and in good shape, I would like to know how much you want for one.
http://classicoldsmobile.com/forums/...t-tank-018.jpg