After listening carefully to all of you and talking to the luthier in Săo Paulo, I decided to leave the SG as it is.

If it wears funny and I don't like how it looks, I'll have the job done.

Cogs, I don't think I'd risk doing it myself, I'm all thumbs and have no experience at all... Since even these ordinary Gibsons and Fenders are awfully expensive here, I wouldn't risk damaging one of them.