Update:

After carefully listening to the noise again today while driving home, I remembered this noise was very similar to the rattles that I had experienced when I first acquired the E53 X5. That noise was identified to be the rattle from the loose rear trunk hatch latch.

The noise is more knocking knocking than tapping tapping, now that I had something to compare with from memory.

I decided to tape up all three latches on the E70's rear trunk hatch with cloth friction tape, same ones I used on the E53 per one of the forum member's suggestion (don't remember his name now, but thank you again for the valuable tip!)

Just test drove it again after the tape wrap on the latch, and the noise has considerably reduced.

The center latch is slightly loose and if I tape it more than once the trunk hatch will only open slightly.

If I wrap just a thin layer then the hatch will open fully without any issues.

But one layer doesn't seem to be enough, as I can still hear slight rattle from time to time.

Definitely a major improvement, and i hope my brain will get used to the slight rattle as I drive it more frequently.

Anyway sorry to hijack minesapasty's thread again, but hopefully my discovery could help others who may have the same rattle issue as me on their beloved E70.

Cheers!

p.s. sway bar link is a wear item so I'll be keeping the new parts once they arrive for their eventual replacement down the road.

__________________
2003 X5 4.6is Estoril Blue, acquired March 2018
2013 128i M Sport 6 MT Space Grey daily driver
2010 535xi 6 MT Barbera Red