The normal early GM switch that you purchase at the auto store will give you a power to the up side or power to the down side or nothing in the middle. They will not work with the newer motors like most of the kits and new cars have. You cannot use a 3 position switch like you would purchase at the auto store for power windows. You have to have new type GM reverse polarity switches. There are some made that look just like the old switches. So, are you replacing a switch in an old system or putting in a new system? Switch must be correct.