Time to break out the torx set… here are the official install instructions for MINI's iPod interface kit.

[ MINI/iPod Install PDF ]

It may also be worth noting that the part number listed on the actual interface (pictured above) most likely isn't the number that you need to order the kit. I would guess that is found on the box itself pictured here.

And finally it may interest some to see who actually produces the interface listed in the lower right corner of the pitcure above.