Replacing Valve Keepers

I'm rebuilding my head, and it's finally time to put the valve springs back in, problem is, the new springs are shorter and stiffer, and therefore even harder to squeeze the valve keepers in. What's the best way to do this, and to keep the valve closed? (Head is off the car)

You need a valve srping compressor. It pushes up on the valve and down on the spring so you can put the keepers in.

I have a valve springs compressor, it's just still very difficult to compress the spring far enough and place the valve keepers on the valve stem. I'm thinking the best option is to get atleast on other person to help, but any more ideas?

nope two people sounds like a good idea. Its always easier with an extra set of hands.