It needs to be removed and trust me and the others that have said the same. ITS A PITA TO GET OUT! Id suggests finding someone to sandblast it. If you cant than burn it a few times and get it real hot than get to work with a wire cup brush or flap discs on a grinder or drill. If your using the flat lid dont burn that as it will warp it.
BLUE WEBER 22.5 OTG,(OBUDS) OVERBUILT U.D.S, MAVERICK ET732, THERMOPEN KNOCK OFF