[General Maximus]

the shub doesnt have to be connect to your outside connection to work dude. You are getting yourself in a but of a pickle because if you are putting a shub upstrairs you need it to work as a router and not a modem. It is the modem but you need downstrairs to get your outside connection. If you can run a cable upstairs or through the floor/wall or something you can connect your spare shub to the one downstairs and continue to use it as normal to connect wired devices to and use it for wireless. You'll have to change a few options like disabling dhcp on it because you'll want your shub downstairs to act as the core router and hand out ip addresses to all the devices on the network.