Maybe a good time to do the valley pan gasket as well?

New belts to go along with the new pulleys?

Do check the drive belt tensioners as well. I'm not sure about the 4.6 but on the 3.0 we have a hydraulic tensioner with bushings that are replaceable.

Cooling system hoses, do check them while they are out.

Diff (synthetic 75w90 GL4) and transfer case (ATF in your pre-Xdrive) fluids?

Trans fluid? (controversial, some do not recommend this, I personally have done it with no problems)

If you have excessive negative camber in the rear, I would look at the rear upper wishbone. It may be whole but it's bushing often deforms and is not centered. also look at the rear locating link, its ball joint boot is often torn by now and joint itself often has play. I would replace both. I have tried it on two X5's now and it has gotten rear camber into spec and closer to new stability both times.

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04 X5 3.0i auto
03 X5 4.6is