Hello there,
if you will change the thermostat look between both timing belt covers below control valve, but bevor you try to change the thermostat you should drain your cooling liquid from the radiator and the engine.!! But look to the position of installation !!! If you will change the water pump remove the left cover from the timing belt and than you can look inside the housing. So now you need a flashlight, or maybe not??
And try to turn the pully on the right below the big cog from the camshaft (grey iron pully without any gearing). normally you can turn the pully.! But take care and don´t change the positin from the timing belt.!!!
