I cleaned and polished a bit of the gunk off the knob for off and on but there is a bit of wear showing around the knob
the base material is showing through. Is there any touch up for the panel and knob where the silver has come off?
So Testors model paint in nickel/silver. Pour a bit out in a small cup or vessel allow it to sit for about 5 minutes so some of the solvent bleeds out. use a small oil painters brush with stiff bristles and you can dab it in and come close to the pattern thats there. However, a thorough cleaning revealed several layers of built up finger grease and the original color was still present. The only touch up needed was the very rim of the knob and a few scratches where the gray under plastic showed through.