About 5 years ago I bought a Les Paul. It was a lovely pure white colour. After a while when it started to look not so pure anymore I started thinking to myself "why didn't I buy a black one?". Anyway, now it's gone from a not so pure looking white to an almost yellowy colour in some places. Has anyone got any ideas how I can get my guitar back to the lovely white that it once was, preferably a method with a low chance of cocking it up and ruining the guitar?