yeah, after a few days, they mirrors were on tight. i didn't have a problem with them shifting around after that. i think also the fact that i used chrome bolts instead of the included ones may have contributed to them slipping around at first.
did you end up putting the bolt caps on? i see you put the foam bolt caps on the mirror arms. nice touch.
hehe.
i think if you mess around with the joints more you may get a bit better results as far as getting your arms out of the reflection and still seeing behind you.