I was being facetious above. That said, I would hope that a guy from out of town who makes an appointment in advance and supplies the correct master install kit and gears could expect to get them installed in one day. If the parts were wrong then it's the customer's problem of course.
Kurt, I see your point, but I wouldn't promise that to anyone. There's just too much that can, and will, go sideways. Also, the tech's have to be able to stop and look at other potential customers issues, consult, advise, etc, to keep new business coming in, so it's not a sterile environment for time and gear setup.