Hi
Replace in pairs generally.
I would suggest o/e parts.
Tend to buy these from BMW
Had so called o/e sent to me in past by Euro & GSF.
Not worth the b@all ache of another lost day getting the
correct parts.
You have come back also. if parts fail prematurely.
Reaction, or thrust arms split regularly on inner bush.
Idler arm is steering.
It adds an extra vagueness to already vague steering.
Is it bush ovalised & braking up or is it loose & needs tightening ?
Anti-roll bar drop links attach to back of damper & down to roll bar ends.
Commonly termed vertical drop link.
Do both.
Diff seals on input & output...join the evergrowing club.
Strip & rebuild is solution....if not noisy or pouring out, it can wait.
Judgement call !
One hanger missing completely on rear box.....sounds familiar, eh Andy
Faz