I've got a 78 xs650 special, didn't want mags so I got some rims from a salvage guy by me. The rear rim he had tagged xs500, no year on it. It fit great, only problem is There is a brake light switch built into the drum. I need to replace it but cant find one anywhere, Is this an xs500 rim or was it mislabled. Does anyone know where to get on? THanks