Thanks Bob, but I have tried something similar. When I first saw warning light I read up on others experience and most problems seem to have been due to sensor in rear suspension - it picks up a lot of wet crud from the road here. So I bought a clone replacement, very similar if not the same as your recommendation and replaced it. No change, so looking at front sensor next, I could see it had received a knock and on removal found it seized. So having now got the old rear sensor which since no change, assumed to be OK and looks identical, I put it in place of the front one. But still error light (and no movement of headlights when switched on).
Next two thoughts, are front and rear sensors identical (I found out from Lexus that they have different part numbers - though they would not tell me what these part nos are, but they do include the rods etc for mounting which could explain that)?
Also when you mention clockwise and anti versions, does that mean if the wrong one is used the spindle would not rotate at all in the right direction when in position?