detent on passenger side mirror

Hey guys, had my truck for about a month, salvage titled truck, but pretty much looks like a new one, ironing out the bugs, anyway, the detent is not there on the passenger side outside rear view, ie it swings full forward freely, doesn't ever "lock" anyone know how to get into these things? the power adjust only works in one direction there too. I can live with that one, just need the detent, how to get to it?

It is a painted mirror, or I would just goto a yard and get one, but I don't want to repaint it, whole truck has been painted, so it is perfect paint everywhere, incl. the mirrors.

Update...

Two weeks ago tomorrow, I smoked a mail box with the mirror in question here, broke the mirror slick off of the mounts, I had to pull the door panel and the mounts from the door. I glued it back together with two part epoxy, worked great; while there though I investigated the detent. It is part of the plastic molding. I put it into regular position and epoxied it there. Also while there I pried the glass off and investigated the power mirrors, one of the wires was unhooked from the motor, hooked it back up and I now have some power functions. The motors are shot, probably froze up from not being used. It does work, just growls at you and works very slowly...