Actually I think I know what I'm going to do now. I'll have to cut away the right side of the dash a little bit, but it should look OK, although I'm going to be screwed when I go to sell the car, oh well hehe.

I decided that I would just remove the bottom plastic tray completely and mount the empeg tray right in the middle. I can get some plastic and make 2 strips, one on top and the other on bottom. I have to do this because otherwise the empeg tall is also too tall and I would have to cut into the top of the dash plastic and I wouldn't have the good screw holes. There's also a large and strong metal pipe directly behind where the empeg will go and I can use the screw hole in the back of the tray and connect that to a piece of backstrapping that will go around the pipe. Now I just have to figure out how to secure the right side of the tray