Can anyone tell me which 2 1/4 inch trackball would be best for mounitng on the third panel of a cocktail cab that has limited space? Between the ones I've seen, Wico, Happ, Ultimarc, they all seem to be roughly the same size (4.5" wide). Are there ones out there with smaller housings? It has to be one that can be illuminated from underneath also using a translucent ball. Any suggestions?