I have never seen the kit instructions, but on my Lance, they removed & patched the pitot hole, removed the lines to the diaphragm, and removed the linkage between the diaphragm and the Hoof valve. The valve obviously stays in place. Add a couple placards, paint the patch, and that's it. 2 hours tops imo including r&r the interior and paint touch up. Maybe another hour for paperwork.
I've seen a few that still have the pitot in place, but the system is disabled. I wouldn't do that, but it may be that the "kit" is just instructions and a placard, which would explain the "reasonable" price.