I have a spring compressor if you want to drop by this weekend.

Lapping is a process of spinning the valve while pushing it against the seat with an abrasive compound. The tool is just a wooden handle with a suction cup on one end. It a good thing to do if you aren't going to have the seats and valves ground.

http://www.youtube.com/watch?v=fhXsH12Rg6s