As I mentioned in post #17...the image of the rear relay locations that belongs to powers1 (he doesn't have any model/model year/build date in a signature)...it apparently is the pre-face lift layout.
I was just reading this information this morning about the
e53 X5's face lift changes (starting with 10/03 build date)...and below is some info about the SCA (soft close actuator) and the rear relay/fuse box layout below...the
SCA relay is the one on the far right in the rear right cargo area:
This is an image of my 2006's rear fuse box...SCA relay is on the purple relay on far right

FACE LIFT layout of rear fuse carrier (10/03-up build date)