Fitting new heater valve
This video shows the heater valve being fitted plus any associated under bonnet trim such as the plastic bulkhead trim that fits around the heater valve inlet/outlet pipes.
To replace the heater valve, thermostat etc the only tools needed were;
1)Long cross-head screwdriver
2)Stubby cross-head
3)10mm spanner (wrench if you're watching this in the US) to disconnect battery earth cable from negative post.
4)Hose spring clip pliers. Large pliers can be used instead but the proper tool makes it a bit easier to shift spring clips which can put up a fight if they've never been moved before.
5)Flat repair washer. To undo large crossheaded radiator drain plug.
6)Socket set plus 10mm socket and small crosshead screwdriver bit. To remove thermostat housing and access rear screws on matrix top panel. See videos.
If you've got any questions let me know via message or comments section.