Car is now fixed and the new water pump works well. Things that I've put in:
BMW composite water pump
Febi Water pump pulley
Behr fan clutch
BMW fan blades
Aluminium Thermostat housing
New tensioning pulleys and tensioners
I am happy t works now. However, the new fan clutch is very stiff and the fan is pretty loud even at idle (and cold temperatures). It's a brand new Behr clutch, and it seems to be way too stiff. With revs, the car sounds like a Mac truck. Do the fan clutched have a break-in period?