Have the repair carried out by your nearest BMW dealer or mechanic at least.
It is hours of pain and suffering.
It is attached to the thermostat housing from memory.
It is also connected to two pipes with O rings and i strongly suggest checking the valley cover for leaks and replacing the o rings.
But if you are very keen, off the top of my head, you will need torx bit, screw drivers, 10, 11, 13, 16mm sockets and spanner, lube, trim tool and im sure there are several other tools i have missed