Well we started it.
Last night we started ripping out the old tile and that continued this morning. There is still a bit more to rip up, like the floor, but we are getting close to where we can start rebuilding.
Unfortunately we found an old termite infestation. They didn't do anything that compromises the integrity of the house but we'll be replacing a few 2x4s. Ah the fun that you discover when remodeling an old home.