Don is right about kinked cables... I just about drove myself crazy when I got my "new" old dash off ebay and none of the knobs would move...
After quite a bit of frustration I flipped the dash over, happened to straighten a cable and it was fine...

The next two however were not and I had to spray liquid wrench into the end of the cable housing and elevate it... within a couple hours they released and worked just fine...
I hope that helps, jordan... sounds like you're on the right track...

~Trev