Some people put an aluminum washer on either side to take up the slack.
I did that in one of mine. I found bearings that fit exactly the width of the wrist pin and made some washers with a few tenths of a mm clearance on each side. Seems to lower the vibration.
There was a thread here a few months back where I got the idea to do it. Can't remember who suggested it but I'd say it is a worth while improvement. Another suggestion was to chamfer the oil hole in the the connecting rod to improve flow to the bearing, next time I'll do that as well.