(It) Is going to be a new design. Check Wayne notes about vertical alignment. I guess it is possible unless someone says otherwise because of xover frequency or something else. You probably will lose a little bass. I am not sure of Wayne's approval, afterall it's a PiSpeaker. (You) Should check max. distance between speaker drivers also. I am not sure about the phase on the low frequency xover/speakers if it is ok or not since they (mid/tweet) will be advanced/forward. Overall I guess you have some work to do.