Proper Install of Flush Valve stems

[Hemi8]

I have a set of Coys C5 wheels and they have the flush valve stems that came with the wheels. Does this look like it was installed properly ("O" ring squishing from the inside out)? The crew that installed them had a hell of a time (they had never installed flush stems before), they installed the first one wrong and had to redo it and another wheel they had to redo 2 times because the valve was leaking past "O" ring. They have been on the car about a year and seem to hold pressure well but I noticed this o-ring a couple days ago. Who makes the highest quality flush stems if I decide to replace these? If it was just an improper install is there a better o-ring or maybe a torque spec the tech could follow (stems came with no directions).
Mike

[MIKE67]

Flush valves look cool but can be a real pain. Buy some extra extension tubes!! I have Gorilla brand VS406C from summit. Mine don't squish out. The stems have an undercut to retain the oring. But the caps don't have an oring (but there is a large chamfer in the housing so you could probably add one). NOTE: The photos are from when I fabricated a bracket to hold the TPMS Sensors.