Hey, yall. Check out the "p-trap" on the pdf.
Ok, so trying to get everybody on board for some new technology when the various tradesmen involved never even see each other could be a difficult task. Best thing for the plumber to do is to pull up a lawn chair and sit there for a couple of days with a shotgun across his lap and try to get the customer, carpenter, tile setter on board with the program. "Can you just move it over an inch or two this way?" No, mam, that's what the shotgun's for. The remodeling contractor's job is to iron out all these gray areas between the trades, but if he's making money, he's running three other jobs at the same time. Also, it's in his best interest to keep people there and not move on and get tied down on another job.
If someone is doing the whole shebang himself, totally ignore the last paragraph.