6lug swap

[HEAVCHEV3]

Everything was going fine until I got to the calipers. Need help.

Ok 6 lug disk brake upgrade 1.25inch rotor 71 spindles. My calipers seem to big they fit over the rotor but it does not bolt up to the spindle.Should I have ordered 71 calipers? I have read on the forum when you have the 1.25 inch rotors this changes the size of your calipers am I right or wrong. I called auto parts store and they only have only 1 size caliper for that year. Does the 71 factory caliper fit both 1 inch and 1.25 rotor. Is there a bracket that I'm missing or something? I'm stuck Does anyone have a part # for the correct caliper 1.25 rotor 6 lug from the local stores.I