LOL this happened to me the other day. Had a rattle coming from my exhaust and thought it was from my baffle fittings as it had come loose and got lost down the road somewhere. After taking the link pipes etc off and shaking them upside down (to no avail but still rattling) I looked on the opposite side and welded to the link pipe is a holder with a square nut loose inside it. Im guessing this is the fixing you access from the left hand side if only I had checked this before taking the exhaust off LMAO.
Pair of pliers and 30 seconds later said rattling nut was removed as it was not being used anyway.
Gosh thats alot of typing I'm bored. Make sure you check your whole exhaust before taking it off
