I think the issue with cameras using MF-glass is always the view finder. IMO the D600 finder is not the best for that purpose, although I took a big series with the D600 & the 1.4/35 Ai-S as you might remember. The D500, although DX has a wonderful grund glass. I wish I could exchange the ground glass in my D600 for the same F6-Type, but I did not find that option yet. Do you know someone here who replaced the D600 ground glass with something better?
Adding to that I always found the D70 / D70s better than the D200. The D200 features a much brighter view finder, but MF was next to impossible for me, whicle I took a lot of MF shots with the D70ies. I later replaced both grund glasses with split prism offerings, obe Katzeye, one enjoyourcamera.
Concerning the building: As long as you keep the roof in good order, no trouble will arise with the basic construction.