Correct on the torque settings, the reason you can tighten the track control arm bolt with the suspension hanging is because it is a metal bearing rose joint and so is free to rotate, the thrust arm bush works on the "twisting rubber" principle and so needs to sit neutrally prior to being tightened, unless it's a Powerflex bush and in this case, no pre-load is necessary.

X5Girl, xxx

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Black E53 V8 on 20's, lowered, drilled discs and poly bushes, strut brace and adjustable sway bars.