Problem solved...there was an obstruction in the low pressure line between the gauge set and the suction port, so none of the gas was reaching the compressor when I tried to charge the system. That's why it seemed as if the compressor wasn't...compressing, because it was not getting any refrigerant....

Indeed I had. Never charge both sides at the same time.

I wish I had done something stupid like that, so I could just do a forehead smack and move on!

This is a 2005 Lincoln LS, and I decided that I only wanted to do this job once, since the dashboard needed to come out to replace the THX valve. I replaced the compressor, THX, evap, condenser and the filter/drier. Essentially I had a brand new system, all the components were new, BRAND new. I flus...