How do you replace the thermostat on a 2001 Land Rover 75?

Difficult to work on and lots of garages wouldn't touch mine which is a Rover 75 V6 auto. I got a garage to carry out repair for about £120.00 including parts.

Difficult to work on and lots of garages wouldn't touch mine which is a Rover 75 V6 auto. I got a garage to carry out repair for about