Having problems with the neutral light staying on when in gear on my K6. The bulb just dims but will not go out. As a new switch is about £50 I thought I would try and repair it. If you remove the araldite type sealer from the bottom of the switch very carefully( the base is plastic) and use a pair of circlip pliers or something similar, you can unscrew the plastic cover. Inside it is a very simple switch with a spring and some brass contacts and a tube to locate the spring.
I just cleaned the dirty and tarnished components and re - assembled and the switch worked perfectly.