While doing some head work (home valve job otherwise called valve lapping) on my supposedly parts bike I looked at the adjusting screws. Given my past experience I am not surprised to find they need replacing. The ends of the valve stems look a little rough and I figured I could take a rubber wheel on a Dremel and lightly polish them unless someone knows of a good reason not to. Keep in mind this is a shoe string operation.
The other thing is checking these adjusting screws for wear is very easy -- simply unscrew them from the rocker and take a look. Maybe even use a magnifying glass for a clearer view ( as I do ). You might want to be super careful and stuff a paper towel in the hole around the rocker arm so if you drop the screw it doesn't fall into the engine. You can't be to careful!
The ends of the adjusting screws. Not real bad but bad enough to justify replacing.
The ends of the valve stems. Again, a light polishing with a rubber wheel to smooth out any rough edges. Any one think that is a bad idea please say so.