On Yahoo groups if your modertor how do you change the group photo?

I started 2 yahoo groups. On one of them I want to change the main picture to a better one. Is there a way to do that? I've looked and haven't yet figured it out. I can change photos in my photo album but not the main group pic.On Yahoo groups if your modertor how do you change the group photo?
Click 'edit' on the group description, In the last section there's a way you can change the colors, when you look to the side of that, you'll notice your main picture, click 'edit' on that and exchange the picture.