You will need a a/c line disconnect tool kit, your local parts store should have them. They are usually made of plastic, and are like a split sleeve that fits the OD of the aluminum tube, then you push it into the small gap in the fitting to release the coil spring that holds the two halves together.

This place has a few different sets:
http://www.thetoolwarehouse.net/c-104-disconnect-tools.aspx

I think one of the bolts for the housing is behind the PCM on the passenger side firewall.

Hope this helps!