Your right, I used small ball joint, and used my drum spindles. They provide an adaptor that slides over the drum spindles that makes the new rotors fit, and The rotors are drilled for both bolt patterns and supply both lugs for the option of staying with small bolt pattern or going to the 5x41/2. I stayed with small bolt pattern.
I have a question regarding the lower ball joints. I am using my OE knuckle for the disc brake conversion. Do I order the lower ball joint for drum brakes? Are they the same size for drum and disc? Or does it matter? Are they different sizes BJ?