Here's how I finally got all of the slop out of my rear wheels. Yeah, I didn't have much, but all this business about tapping screws and whatnot seemed... excessive, and expensive. I figured it just needed the right shim and a simple way to keep the bearings captured.

On the hubs, where the pin goes through, I used a 3/16 axle shim (these are ridiculously thin), then a .030 alum washer, then the hub, then another .030 alum washer, and another 3/16 axle shim. After installing the pin and capture screw back in, there was no slop there. But, the bearing still allowed a little play. So I used blue painter's tape, wrapped it around the outside bearing only, trimmed it up with a razor, then tried to put it back in the hub. I had to peel away tape until the bearing was just able to be crammed back in there... there was only tape on about half of the bearing when I was able to get it to fit.

Now, the only minuscule amount of play, and it is virtually NOTHING, is in the axle pin attaching the rear ARM to the chassis. I could shim this away, I'm sure, but I don't want any binding at all there.

If you try this, and you still have slop, then it's not coming from the hubs/bearings - either you haven't assembled the CVA/CVD correctly, or your hexes are worn out, or your wheels are, or the holes in the arm where the pin goes through are messed up, or.... something!

If I could post a video, I would.. I may, if I figure that out.

But these suckers are rock solid now.

Funny, now the fronts, which seemed pretty good, are awful in comparison. Time to get out the shims....