Yes, those are the ones. I use fixed 1.5 deg arms on my 'S' as adjustable ones are not allowed for historic rallying. Those bushes enable the camber to be finely adjusted.
Personally I see no need for adjustable arms on a road car. On the track, maybe, where totally accurate geometry may give a few 1/10ths of a second per lap, but on a road car do you really drive to those ultimate limits on public roads?
