i need some help

i have an 07 mustang and I was recently changing the rear brakes on it. when i took the calibers off in order to put them back on with the new brake pads i had to use the c-clamp to pust the caliber back to fit over the new pads. now my back brakes arent working at all. theres no air in the lines everything is fine. but i found out that apparently you have to use some certain tool to push the caliber back on some newer model cars. what should i do. did i royally screw my calibers up by using the c-clamp to push them back withouth the tool or can this be fixed easy without alot of work. need some input thanks.
 
You'll need new calipers, sorry. Brakes are one area where you definitely don't want to start rigging things to work, such as attempting a repair of a damaged caliper. You're not the first person to find this out the hard way, unfortunately. :welcome: to :SNSign: though!