Hi Kristin,
I was hoping to give you a few christmas nuts, but, although edible, they turned out to be red herrings !
I was in my local music library recently so I thought I would look up "Schwarz - Orgelbauer"
Red-Herring 1) I found an article in a german music reference book, but then found the same article in the Grove Dictionary of Music (see attatchment)
Red-Herring 2) The only reference to Schwarz in South Germany was in Üblingen - which I can't (so far) find in any internet search machines !
I shall keep looking ! You mentioned some time that the Schwarz organs were still around. Can you let me/us know where they are, perhaps we can trace him through them.
Happy New Year, and I hope you find all your nuts !