Hi Ron,
My best advise would be to use several grades of "Micromesh", readily available on ebay.
It comes in several grades and can be bought in a set, from a few grades of cushioned abrasive up to a full set of abrasive pads, finger files and a polishing fluid with cloth.
Good news is that they don`t wear out like sandpaper or emery cloth.
Here is a link to a basic pack. There are many other options as I said, just look around ebay.
Super shineyShould you choose to leave your Spitfire unpainted you will have to use a clear coat over the whole model to prevent oxidization.
Here is a picture of two of my Lancaster spinners. One untouched and the other with a basic clean up using micromesh, sufficient for painting.

With just a bit more effort, you`ll get even better results.
Hope this helps.
Regards
delboy271155
(Derek)
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