you talking about the intake and exhasut valves in the head
well once you have the head off and both manifolds off you get the valve removing tool that presses onto the valve face and the other end you clamp down and that compresses the valve spring then there are 2 little collets they are easy to come out harder to put back in best way is 2 small screwdrivers one with a damb of grease on
holds it on to the screwdriver
once they are out unclamp the spring slowy as it will have a bit of force there remove the tool then the spring and the valve will just pull up nice and easy
easy once you know how
used to have to lap the new valves in but dont do that so much now that could take hours
