I believe the black wiper arms/ face lift cars are bolted onto the spindel and not snap on type like the pre face lift cars have.
The black arms have a cap under which is the bolt and spindle itself is threaded on top for the bolt. This was surely the FL fix for the arms detaching themselves inflight!
Although @Michael Kaye has a face lift car, it’s a known fact that earlier FL cars ended up with the surplus Pre FL parts like chrome arms, 5 black slat kidneys etc.
Either way, a direct sway is not possible.
The black arms have a cap under which is the bolt and spindle itself is threaded on top for the bolt. This was surely the FL fix for the arms detaching themselves inflight!
Although @Michael Kaye has a face lift car, it’s a known fact that earlier FL cars ended up with the surplus Pre FL parts like chrome arms, 5 black slat kidneys etc.
Either way, a direct sway is not possible.