Suggestions on HDTV viewing height

I just bought the Mitsubishi 73" DLP and was looking for a A/V stand that would house my audio components and of course, the TV. Salamander makes a few good stands but the triple shelving (65.75" W) comes in two heights 31" and 21". I feel the 31" stand will place this large tv up to high slightly above eye level whereas the 21" is almost eye level. My viewing distance is 13.5' and the room is 18 by 15. Any suggestions would be of help