Deleting faces/vertices by UV map

I have a stadium part, something like this (the upside of image).

I want to delete every part of this model except seats. (bottom left of mapping) I want to do this by UV map, as the other way would take so much time and energy.

How can I do that?

Btw it’s blender 2.43
edit: got it thanks. I used a later version and voila.