The issue here isn't valve clearance. 22R's use adjuster screws that ride directly against the valve ends. Those screws don't usually line up perfectly with the valve ends, which is expected. Being off a little doesn't hurt. If they are out significantly, using a thin washer/shim on the shaft to move the rocker arm over slightly makes sense.

In my case, the rockers farthest out of alignment aren't the two riding against those factory spacers, so replacing them won't help.

I switched my rocker arms around so fresh, unworn sides ride against the towers. That didn't make much difference, so wear, as I suspected, isn't an issue.

I've ordered some shims from McMaster-Carr.

Here are pictures of #1 intake, needing somwhere around .050" worth of shimming to be centered:

http://i859.photobucket.com/albums/ab154/flyingbrass45/rebuild/DSCF4022_640x480.jpg

http://i859.photobucket.com/albums/ab154/flyingbrass45/rebuild/DSCF4023_640x480.jpg