Where did you get the parts for the DIN plug? I have been looking to make one so that I can use Plantronics headset 480, but can't find the correct parts without destroying a good lower cord (too much money for that).
The Plantronics 480 works great, I make the adapter on ebay that works for most computer style headsets (just search for harley headsets).
For those diy'ers here is a picture of the wiring. You can find both 5 and 7 pin plugs on ebay, (search for "5 pin din" or "7 pin din") both will work since the first and last pin are not used on the 7 pin.