Those rubber pieces on top are coil spacers that were already on the struts. Take them off and use the new ones you have. You can go up to 4" on an '05 4X4, but you will require upper control arms and you would have to get the other 2" of the lift from the preload of an adjustable coilover. If you do that, I'd recommend Dirt King or PRG uppers and Bilstein 5100's.
'07 CC 4X4
banks ram air w/ tb screen removed, banks monster exhaust, prg minilift, PRG UCA's, PRG endlinks, 5100's all around, DK shackles, Brake motive brakes, headlight mod w/ JB switcbacks, Legit 55w 6000 hid's (lows and highs), modded tail lights, street scene grille shell, xd diesel 20x10 w/ terra grapplers, pinch weld mod, axle vent mod, BW pocket flares, PD'd stuff, BL step rails, SM designs bezel kit