Alright a/n/ons. I know you all aren't necessarily a "tech support" board but I would like a second opinion from strangers on the internet who like to talk about bicycles. Pic related is where my rear derailleur used to be attached to the bicycle frame. The piece still on the bike looks like it is foreign to the frame, but when I check out shimano derailleurs (which this one is), I can't find any that look like they would have this piece for connecting to the frame. Is my goose fucked, or can this be removed and replaced by another derailleur.