Re: Collapsed wheel bearing?
I'm a bit confused as to the problem you describe. Bearings usually don't "knock", the noises they make are usually described as "rumbles" or "whines", depending on pitch. Knocks however are 99% of the time caused by Ball Joints. In your particular case (98 AU, Series I) the most common problem used to be the upper A-arm ball joint causing the knock, although the lower ball joint, the steering rack inner tie rod and any of the bushes (of upper and lower arms) I've also seen fail. I would remove the 18mm nut and bolt that join the upper arm to the steering knuckle and that way isolate and check independently upper and lower arms.
If you still want to check the bearing, just remove the wheel, caliper (2 x 13mm bolts) and the disc. Rotate the hub by hand and check if it feels rough or noisey, this will tell you if the bearing is good or not. To remove the bearing, take the centre cap of the hub off and remove the 36mm retaining nut. The hub/bearing assembly is one unit when you buy it. The old one will more than likely be seized onto the spindle and you'll destroy the bearing when trying to pull it out. Happens to me every time ! cheers