When I received it, I measured 22.2 bottom and 21.8 top, on my fm058, and bought rwc hardware to suit.
As you have found with the too-long bolt issue, my top bolt would bottom out before it tightened on the frame. The best solution would be to get a slightly shorter bolt, but I didn't have one at hand, so put some washers in there to make it work. Seems to have worked ok since I did this (about 9 months ago). I suspect that perhaps the frame designer intended that we should put 22.2 hardware in that top mount, and then spread the rockers slightly to make it fit - then the stock shock bolt might work.
The play referred to above is a separate issue, where the outer diameter of the stock shock bolt is a tiny bit too small. My bike has this issue, but it is very very subtle. So subtle that it was very hard to find. I certainly couldn't see any movement. It doesn't seem to be getting any worse, so I am in no hurry to fix it. I have intended to replace the bolts with something lighter at some stage.
