STFF! Oh, heck:
I'm 99% certain Miele bikes were Japan or Taiwan made, which means the bottom bracket is standard English threading. To check, look at the bottom bracket cup: it should say something like "1.37 x 24". That's English thread. If it says "36 x 24" it's Italian thread.
If English thread, the fixed cup is left-threaded. If Italian, the fixed cup is right threaded.
The spindle length is the other variable. Measure the old one to find out. You want to know dimension "D":