Quoted from pinballinreno:So far, I have it, plus or minus 1/16" or so.
There's a saying I always try to keep in mind when doing these adjustments, because I know exactly how you feel -- you want it dead perfect. The saying is 'Better is the enemy of Good'. It will never be perfect no matter how many times you change it. And if you keep messing with it, you will make it worse or break it. I think that is what that saying means -- if you're at Good, consider leaving that way or suffer the consequences.
UPDATE: I added this because the online dictionary said it so well:
The demand, desire, or insistence for perfection decreases the chances of obtaining a good or favorable result in the end.