Another suction cup success story here! Though I forgot to reinstall the Torx screw for the driver side cover... don't think I'm going to risk removing the mirror again to do so because it's a bit overkill? Clips seem plenty tight.
Be sure to check the auto-dimming mirror function (I've found parked forwards in a garage during the day with the door open behind you will activate the dimming), blind spot LED (lights will very briefly self-check when ignition is set to RUN - engine not required), and defrost heat (just feel them after a few minutes) for your mirrors after reconnecting them. Otherwise the instructions posted by Trix are spot on.
I checked my passenger mirror by pulling the corner back and shining a light in... only after I already removed my driver side mirror (which caused the wires to disconnect, stupid me). On my passenger mirror, the blue wire was nearest the truck and black wire on the outside. This is how I decided to reconnect both mirrors. Hard to say if it's correct since the connection could be oriented the same on both sides (meaning the driver side could need the blue wire on the outside and black on the inside to mirror the passenger side). Either way, how I connected it seems to be working, so maybe it doesn't matter.