I bought a CR-Tech box off ebay for £78 - just checked but they don't seem to be listed for the X5 at the moment :(
When I fitted it I was very impressed , much smoother and more responsive. I think you quickly get used to the extra performance though, it wasn't slow before !
I got a set of Bosch Aeros off ebay - I can't remember exactly how much i paid - about £15 I think .
They are excellent but if you do put them on then remove the U shaped plastic piece from under the driver side arm as they will miss areas of the windscreen if you don't !
I cannot see anything bolted to the dash support bracket neither front or back - providing I am looking at the correct bracket !
I tried to load a photo but couldn't , will try again.
Oh - not in the engine bay box - anyone else any ideas ?
I suppose I should dismantle the lower fascia below the steering wheel but I can find a couple of retaining screws but when I remove them the panel doesn't appear to want to come off .