Narrow front baffle on 4Pi's

Hi Wayne and others,
After hearing a pair of Thermionic 3Pi's a while ago I am very interested in building a pair of these or the Theater 4's for myself. My only problem is that the wall space I have for stereo equipment is limited length wise in the room. I was wondering about using a narrower front baffle and compensating by making the speaker taller. Can you recomend guidelines for what would be the best compromise? For me the narrower the better, but of course the main objective in making them is to build a great sounding speaker and I don't want to lose that by using a poorly designed box. Otherwise I may just go with the 2Pi towers which I haven't heard personally... how would they compare with the Thermionic 3Pi's? (I would be using the speakers primarily with an OTL tube amp but I also like to play with PP and SE designs so compatibility is an issue).
Thanks for all the wonderfully simple and flexible designs Wayne, they are a blessing for the budding DIYer.
Doug

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