How do you replace 94 Jaguar XJ6 valve stem seals?

To replace the valve stem seals on a 1994 Jaguar XJ6, first remove the valve cover to access the cylinder head. Then, use a compression tool to hold the valve springs in place while you remove the retainers and springs. Carefully pull off the old seals and replace them with new ones, ensuring they're seated properly. Finally, reassemble the components in reverse order, making sure to torque everything to the manufacturer's specifications.