Assuming we're keeping their normal motivations the same...
Glory still wants to get out of here. The mayor would probably offer assistance to her as long as it DOESN'T open all the portals and destroy the earth.
The Mayor actually seemed to legitimately care about his city. He'll get Glory out one way or the other, but ideally by the least destructive means possible.
Angelus seems to revel in chaos. He and the Mayor would probably not get along since Angelus is too disruptive. However, A might enjoy the chaos resulting from Glory's success, so he might assist her.