Wilwood install question

[GeoffP]

I started installing my Wilwood brake kit last night and can't get the caliper to center on the rotor. The rotor passes through the caliper diagonally. I'm guessing it's a mounting issue with the adapter bracket. I used the washer(s) specified by Wilwood's instructions (wondering why they were needed, but wanted to follow the instructions). This makes the bracket face diagonal to the rotor face. It's not parallel to the rotor like you'd think it should be. My car is a factory drum car, so I used the hardware for a drum spindle to mount the caliper. The variance isn't huge, probably 1/16" - 1/8" What's considered acceptable?

Thanks!
GeoffP
68 Camaro LT1/T-56 4.10
87 Camaro IROC-Z LT1/4L60E 3.23