David , I was able to take mine apart . Then I cleaned the contacts . Put in some dielectric grease and reassembled .
If you look at the switch case , there are what appear to be plastic rivet heads . Its actually a plastic pin which is melted to seal the switch case together. I carefully drilled the tips of this "rivet" . Then I was able to open the switch . When you put it on the bike there are two screws which hold it together as well as on the bike .
Be careful when opening . So you dont let anything fly out and become lost . Its been quite a while since I did mine and its worked fine since . But I think there is a small spring that could be lost .
maybe this will help you . Also Aspectone is parting the 82Aspy(in for sale section ), perhaps it has the same switch .