those look similar to the pins over have worked on Allison transmission, it may be an Metri-Pack 280 female terminal. Could be wrong but its most likely it, GM uses alot of Metri Pack connectors. You can find these at a local NAPA. Maybe take your mirror and go to napa see if they have metri pack terminals and see which one fits the width and thickness of your male terminals
let me know if any of you all get a loud thump from rear end when going off road over abrupt terrain or a speed bump, i think the shock isnt long enough in the rear but I need someone to second that