Unimog Club UK

I took off the door tops and rear screen because I want to try and clear them up a little.
They are in excellent condition but the plastic has gone a little mysty.

Has anyone done this with success?  And if so what product did you use!
I have been told to try brasso, but im not sure about that?
It will be a shame if they can't be saved, as the canvas is like new.
Thanks for your help.

Cheers
Shaun