Hi top maintenance

[ChrisG]

Hi folks,

Just getting my trusty Dorris sorted for summer and want to clean up the hitop.
Its white but with a few marks, scratches/stains and filled in holes from previous owner (awning blew off I believe)

Anyway, getting van resprayed next year and want the hi top to be just as pristeen.

So, what can I use to clean it?

Can I re paint it? Use a polymer paint for example that you use on fibreglass?

Any advice would be grateful

Regards
Chris