My toilet rough-in is 13.5 inches. I purchased a Toto Drake and it looks there will be a 3.125 inch space from the wall to the tank, which doesn't look good. Does anyone know if I would be able to use a Toto Vespin with the 14" unifit instead? How much room would there be from the tank to the wall? Are there any other choices? Thanks for your help.
You can download the spec sheet (includes a dimensional drawing) from the toto web site. Note that the water supply may have to be moved for the Vespin, as with the skirt, a "normal" supply would be behind the skirt and you'd have no access, if you could set it. I have a Vespin, but I don't remember where the actual flange was positioned (it was not standard), so I can't just measure it for you. Get the drawing to be sure, but I think it would just fit.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013