Gandalf -
The stock GT5 and GT5-S mirrors are Vitalonis, mounted on the door skin as Dennis says. The Vitalonis are somewhat different than the mirrors shown in his photos however. The stock mounting location is also a little higher - it's on the upper door panel - the one that is roughly at a 45 degree angle.
In any regards, it doesn't matter as rear visibility is pretty poor. The real wheel arches being as wide as they are pretty much block a good portion of the view.
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