I did my water pump a few weeks ago and left the rad in place... was a bit fiddly (especially getting the fan back onto the pump) but do-able... I think you need to unclip the bottom piece of the fan shroud, this is done from below, and then you undo the 2 bolts holding the rest of the shroud to the radiator and it just lifts up and out (as best I can remember)... thinking about it you can probably unclip the bottom bit from above and get it out but it is an easy job to take off the bash plate first