Haynes manual says remove bottom hose on radiator and the hose on the thermostat leading to the radiator, and to direct the water flow from the hose into the thermostat to flush the engine block. However, I have done this and the water just seems to go to the reservoir and back through the radiator.

Is there another way of flushing the engine block that will get the water flowing through?!

My plans are to put some Holts speed flush in there and get a few miles done, then I am hoping to replace the thermostat when I get some jointing compound (the tub I have has separated and dried out :S) and fill up with G12+ and de-ionised water then.

You need to remove the thermostat first!

Thanks, another Haynes manual error or omission. That's what I guessed it might be, closed thermostat stopping flow.

Now my heater matrix isn't getting warm. Filled slowly, ran engine for a long while at idle, tapped and squeezed pipes. Guess it needs some more effort to get it filled with water. Edit: just noticed no water in header tank oops. Need to wait for it to cool and top up. It looked like it did have water in and is difficult to see through, I guess I got caught out by the tide mark left by previous coolant.