You can space 2.0 Calipers to make them into 2.8 Calipers. You also need some spacers when mounting them, and you need to remove the dust sheilds too. Burton's do a kit with all you need. But yeah, once the calipers are spaced, or you have 2.8 calipers its just bolt on and bleed the system.
The Land Rover Master Cylinder fits the 2.0 Capri Girling Servo. It's not recommended unless you are fitting bigger calipers though, e.g. from the Granada/Mondeo.