Any question answered...

I have used acetone before with no ill effects.

be cautious though because some rims have a varnish/clear coat/protective layer on them that will rub off with the acetone. One of my team mates tried to use acetone to rub some glue off the sidewall of his rim and rubbed this off which left him with a shiny spot on an otherwise matte rim. the opposite could happen as well.

Just going to clean up the brake track really- I don't think there is a clearcoat here?