
Pretty std stuff:
Jack up and support, remove undertray and OS wheel arch liner
Remove aux belt
Find the hole in the engine back plate above the exhaust flexi, and insert the big pin, turn the engine over forwards till the pin drops in to the lock hole in the flywheel (there appear to be 2 - this is not easy on your own!), remove the crank pulley bolt (not as hard as a 2.0, as it's not thread locked). Remove the locking pin, and crank pulley
Support engine, remove the engine mount and top cover, then the bottom cover and engine mount bracket (they have to be removed together), then belt retainer and crank sensor.
Time up the engine - easy as all at the belt end
Undo the belt tensioner and remove the old belt, tensioner and idler
Drain the coolant (there is a drain plug on the back, but it's above the drive shaft and all but inaccessible) - we just split the coolant hose just under the crank which worked well.
Remove the water pump - about 6 bolts, then mine needed a good levering to get it to release - there is handy lug at the top front corner, but it required a long jemmy bar to get it moving

Refit water pump - the OE one came with 2 bolts which are screwed into the gasket and make it easier to locate
Refit the tensioner loosely, but with the retaining yoke engaged on the spigot, but not the idler
Fit the new belt to the crank, then up the back run, keeping it taut, then over the cam, and then refit the idler and tighten the nut
Turn the eccentric adjuster with a 6mm allen key till the pointer lines up with the centre of the yoke - they come fitted with a pin in this position, so you can just do it till the pin is loose - tighten the bolt (whilst still holding the allen key - otherwise you let go and the tension is all wrong!).
Remove pins, turn engine over forwards 3 or 4 crank turns and re-check timing and tension
Put it all back together. Haynes gives 35NM + 190 deg for the crank pulley bolt - use the flywheel pin again to lock
Refill the coolant - there is a bleed screw on the heater hose and another on the thermostat housing. We managed without a header tank - put coolant in tank, seal the top with your hand, undo the vent pipe from the rad, then blow (hard!) down the vent pipe - this pushes the air / water out much faster.
Re fit aux belt
Re-start engine, and marvel at how quiet it is, and how well it pulls now

When I do the 307 (still quiet....) I will figure out the stretchy belt business!!