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I can think of several ways. but first, do you mean like a ball lift elevater or a compartement elevater like in buildings? cause they can both be made with the same principle. i take to red connectrs and attach them sideways on the chain with as much space as needed, and build the elevater off of that.
If you are talking about a ball machine, here is a good instructable on how to build the lift. If you want it higher just add more to the tower and add more chain.