Currently running 1.1 jail broken on ATT, phone is an original 1.1.

Installer update a few weeks ago broke my installer so i need to restore anyways.

Seems like 1.3 is pretty compatible and stable now so my question os what is currently the best way for me to get to 1.3?

Also if at all possible a method that does not use wifi, we dont have wifi in the dorms where my desktop is so I would have to borrow a laptop, load all the tools on it and go to a lab.