I approve thisThat's not possible in IP.Board, or any other forum software I know of.
What I could do is allow Guides to set their own user title. Badges can only be set by post count or by group (e.g.: all admins and mods have Yoshi badges, and everyone else is on the post counter-based badges), so you won't be able to change that, but you could edit your user title - the text that appears over your avatar (or personal photo, as IPB calls it).
I haven't touched the ranks. All I did was edit my user title. Normally, they're synced with your rank, but I can use my admin powers to make mine whatever I want.
