There are two ways to do it, the first is as Liv suggests above and edit your S2 layer, but if that's all you want to do learning how to do it might be too much (it's what I'd do, I started hacking S2 for just such a little change).

The other way is through custom CSS-you've already removed the text to the archive links, but you can simply hide them from display completely.


.navheader {display:none}

should work