This was passenger side mirror. Had to remove door panel taking the power window/lock bezel and hand grip cup out of panel. After panel is removed you can get to mirror mounting bolts and power plug. After it was removed from the door, I opened the back panel of the mounting bracket with torx driver. Then there is a water seal to remove to get to the phillip screws which mount the mirror arm to the mounting bracket. In my case these had vibrated loose, freeing the mirror from the detent. I just replaced them and adjusted the 2 screws which control the detent pressure plate so the mirror would hold in the detent, but swing away with the same pressure as the drivers side. Then just reverse course to put it all back together. Took me about 2 hours just because I don't have good tools to remove the door panel clips. Had to be really careful with those things. A good mirror from salvage is about $130-145 and a new one is $250 so it was worth it. Good luck on yours.
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'97 2500 Extended cab 4x4,automatic,285/75/16 BFG ATKO, M/T Classics,Prime Loc, sprayon bed liner, Rancho 9000s, Alpine CD Changer, Visor, diamond plate running boards,tailgate and bedrail protectors, Geno's cup holder. Guages coming.