https://www.the-t-bar.com/forum/21-david-aiketgate-s-guides/90064-starter-motor-how-to-remove-replace
It can be a bit off-putting, but overall not too bad a job once you familiarise yourself t the layout.
Yeah, have to say, it is always nice to know if the advice cures a problem or not. After all, it's by sharing help and advice that allows us to keep these cars running without too many trips to the garage.
I know if they are very cloudy, it's a fine sand and polish to get a near perfect look. But unless you lacquer it, they will become cloudy rather soon. I have used the 3M headlight system, which is just progressive sanding and a finishing polish. But have used plain wet and dry and had as good a result. If they are not too bad yes Something like Renovo rear screen polish would do as would a fine cutting paste. You can find a host of solutions on YouTube some good advice, some complete fantasy.
Since I didn't have a clue what fixed on the original post, I drilled them out and used rivnuts ( had been waiting ages to use this tool) to thread lock some studding in and used standard wing nuts and a flat washer.