Pulling the front brake rotors off the XKE / E-type is relatively straightforward. There is a half-shaft with a threaded end to which the hubs are bolted. The large bolt inside the hub is castellated and secured with a cotter pin. Now, since the cotter pin is inside the hub it has to be withdrawn through a small hole drilled through the hub. Once the cotter pin is pulled out, and assuming the shaft has been well lubricated, the nut is easy to remove and the hub and brake rotor can taken off the car easily.
As the front brake rotor is bolted to the hub, it comes free at the same time as the front hub and then has to be separated from the hub. I found that an impact wrench was useful in freeing up the nuts and bolts that secure the rotor to the hub. Once I had the old rotors off the car I could compare them to the new replacement ones and there was really a huge difference in thickness. I am not sure the old ones would have taken any further machining – lucky for me that new rotors for the E-type are pretty inexpensive. So far – so good.