Bugged Guitar in Britechester can't be deleted. Help:(

I had a guitar stuck in mid air too, it was at the festival grounds so every festival held there I'd see the gravity-defying guitar hanging there. lol
I couldn't get rid of it and eventually got tired of it so I painstakingly moved each household and house into a new save game. Doing that borked a couple of branches on the family tree but the guitar was gone. I may go back and try the mods to see if I can get rid of the possessed guitar in the original save. Thanks for this post and your solution!