recently bought the front knuckle as well. After installing I relized that the disc caliper from 3racing for D4 can't even fit on. The hole on the hub is totally out of alignment. From the same brand and same model can't even fit, what a failure.
Finding you are ripping out the ball stud from the rear hubs. Well here's the upgrade for you. They dont just look great, they work great to and only take minutes to install. Highly recommended upgrade.