A few things come to mind. #1, make sure your caliper is installed correctly. Proper side of the mounting plate, etc. Get a ruler or tape measure out and verify from a known point that is the same on both sides. Spindle mount, king pin, whatever. Just make sure you are measuring from the same point on either side. #2, measure your offset. It's easy to do. Place a flat piece of metal or wood across the wheel edge of the backside of your rim. Take a ruler and measure down to the mount area. Repeat 3 more times. While you're at it, verify your rim diameter.
Verify what you got before you throw more money and parts at it.
