Notes:
ingenious: one simple part replaces setting-lever spring, yoke, and yoke spring
differences not known between 575, 762
Gruen lists two balance staffs and two lever arbors for the equivalent Gruen 179. Maybe this lead to two Alpina calibres within the Alpina-Gruen Guild.
The additional Gruen designation 179 on the earlier Alpina 762 makes more likely that it was finished by Gruen, while the later Alpina 575 was purchased directly from Universal.
Movement registers and staff lists contain only the base calibre Universal 259, and this makes further investigations difficult.