Another thought. Glumpler is quite unusual as a name and if you look in dastelefonbuch you will find that there are only nine entries for the whole of Germany. It might be worth writing a polite note and asking if any of them originated from what was Czechslovakia (Bohemia, Czech Republic). The German speaking population of Czechoslovakia was expelled from the country in 1946-47 and the survivors settled in various parts of Germany. It would not cost a lot and the worst that could happen is that you get no answer.