My plastic swivel broke. It was part of the timing advance mechanism mounted at the top of the throttle tower shaft and there is a stainless steel double threaded control rod with slotted end through it, which connects it to the timing advance. The parts list shows it as part number F499026, but no longer available. See Force parts book exploded view of the powerhead, item 16. The broken one has the mounting stud and control rod offset from each other. Should this swivel be connected to the timing trigger side or the tower shaft side? Other people have worked on this engine and moved things around.