You can remove the water pump without removing the radiator.
The Moss and Rover 4 speed engines are mounted further forward than in a 5 speed Plus 8; however, the 'nose' of the water pump is not as long so clearance is ok.
You need to remove the water pump fan belt pulley and the alternator. Make sure that you drain the water out of the block using the drain taps or plugs on either side of the engine block.
The are a number of 1/4" UNC set screws around the water pump as well as some long 5/16" bolts that bolt the water pump and timing cover to the block. Beware as these screws and bolts can corrode into the block so go easy. Some of the bolts and screws are 'hidden' at the base of the pump and not easy to locate.
Rover used to spec a type of thread lubricant for the set srews and bolts. It is in the Haynes workshop manual for P6 Rovers and is a type of Bostick impact adhesive; it looks, feels and smells the same but possibly a tad more 'runny'. The purpose is to provide a barrier between the steel bolts and aluminium block thereby holding back corrosion. I use stainless and the approved thread lubricant. You'll find stainless bolt kits on eBay.
If you need any further info, just PM me.
