Cleaning bezel and tray

I am wondering how to restore the fron bezel and tray of my older cd-rw. They are yellowish from age and smoke.

THanks

try isopropanol alcohol or something like menthylated spirit ,white spirit or any LIGHT alcohol based spirit I prefer isoprop.Just take care none gets inside.Although yellowing from age is practically impossible cos its the plastic thats stained not the surface.