How do I take off the front disc on my 1999 Mercury sable?

To add to bikertrash's excellent advice, the size of tool to remove the caliper from the bracket is 12mm. Once removed, the size of socket needed to remove the caliper bracket is 15mm. I would recommend using a 1/2" drive socket and johnson bar to remove the caliper bracket, since it will be tight to loosen. Hope this helps.