The trim that's around the radio is held on with clips. You have to get under the trim with something (maybe a screwdriver covered with tape) and pry out. After you get it started it should just pop off. After you remove the connectors from the trim, you'll find some screws.
Thank you KiaMech.... can you send me, if it's possible, many photos step by step to remove the trim?
to remove the trim where i start? to the top or to the bottom?
Sorry for my english.... i'm italian