Mell,
You would be able to answer at least one of your questions if you were in possession of a schematic. It's an absolute must when you want to repair or investigate issues with your specific models. Please get one- either from the internet or through a request on the Neumann pinboard - Neumann usually sends a PDF file within 24 hours.
I usually connect pins 3 and 6. Though theoretically, both pins are interconnected inside the mic.
B+ is an old term from the DC-battery era of electronics indicating the plus pole of the battery. In the case of condenser microphones, B+ indicates the plus (high) voltage coming from the power supply which supplies the tube's plate voltage, and the capsule polarisation voltage.
The Neumann schematic indicates with a picture the proper sequence of pin numbers: pin view of the (male) connector pins in the bottom of the mic. "Pin View" means as viewed with the pins visible in the bottom of the mic staring at you.
Specifically: Pin one would be at 5 'o clock, and pin five at 7 o'clock. The configuration inside the female cable connector would be the mirror image of this: pin one at 7 o'clock, etc.
