There isnt a right or wrong. The stages are intake alone, then 4 hole, then open. Each one will effect cylinder to cylinder distribution, overall power, engine response at different rpms, and idle characteristics to some extent. There is no "right" or "wrong". Just what your engine likes. I find if you really need a spacer, you have the wrong intake on there. My advice would be the open one will give you more plenum, and help the air turn better, but give a lower signal to the carb at idle and low speeds. The 4 hole will lessen the bad things, and give you a little more plenum area. So dpeneding on cam, compression, gearing, and convertor, go with what gives you what you need. Better response/low end = 4 hole. Better rpm potential and over all horsepower=open.