You finally had some extra scratch and bought that vintage Hengstler you've had your eye on? Now you want to set your TK number or make your counter functional, but don't want to risk damaging it?   Follow along and gain confidence to perform some simple work on your counter.  I will disassemble, set numbers and perform modifications to a German Hengstler counter.  This particular counter is likely pre-WWII because it has a large eagle logo.  When WWII started, the Hengstler compa