Thanks for your response. Normally, that would do the trick. But we have ONE WSS top-level site and at least FIFTY subwebs off of it. (We are using the one top-level WSS site as the homepage to our employee intranet, and all the subwebs are for the departments and other stuff.)
Now that we're going to be using a Portal site as our interface, I need to convert most of the subwebs into top-level sites so that I can 'connect' them to the portal site. That way they will each have the 'Up to Portal Site' link in the corner instead of 'Up To Our Existing WSS Site That We're Using As A Homepage.'
If I just connect the one top-level site to the Portal site from the location you mentioned, users would have to first go Up To our existing homepage and then go Up To our Portal Site.