i'm having a big problem with brakes, HELP!!

[hotrodder]

I have a 63 fleetside swb that I'm building. On the front I have installed 72 dropped spindles from CPP. I bought rotors, calipers, and pads from O'Reilleys for the same year. When the calipers and pads are put on the rotors it is impossible to spin them. The largest braker bar will not budge them. Remove the calipers and pads and everything spins freely. I went back to O'Reilleys with the problem and got the old story well that what the computer calls for the part numbers are correct. Obviously there is something wrong somewhere. Any ideas?