I just got a fender, and when I removed the little film and sticker off of the pickguard, the area where the sticker was is considerable brighter than the area around it, which appears yellowish. Is there a way to brighten the whole thing?
i doubt it. the pastic on fender pickguards ages with time so it's not just on the surface.

most people think this looks cool, i have a 20 year old strat that now has a very creamy, yellowish tinge on the pastic parts and it looks great! some fenders are sold new with 'aged' plastic parts.

you should find that the area under the sticker will age gradually but meantime you have to live with it. i wouldn't recommend trying to brghten up the rest of it, probably make things look worse.
I've been imitated so well I've heard people copy my mistakes.
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