If the heads are off the car i would go with the big c-clamp style. Last night i stripped 2 sets of heads in under 5 minutes with one. It will take longer to assemble because i correct the installed heights on all the valves but still not very long when you figure out which shims you need under which valves. It presses directly on the bottom of the valve and is adjustable on the other end to accomodate different size retainers. To aid in removing the keepers, put a rag under the valves and on a flat surface quickly strike the retainer with a Ford wrench. Use a big socket to transfer the energy from the hammer to the retainer. Dont put something rigid under the valves when doing this or you could bend the valves when hitting them! The rag will absorb the excess energy. Once you do this the springs will be very easy to remove.