Just did this with drilling holes in the little handles. From there, I put a small zip tie in it along with a paracord, which has a key ring on the other end. Great mod and about the first one I've done to my 2011 SCrew.
2011 F-150 XLT Chrome Package 5.0L SCrew
Interior LEDs, Reverse, Cargo, Headlights, Fogs, License Plate Lights all LEDs, TruxPort Tonneau Cover, Fold-Down Back Seat Mod, PTM Mirror Reflectors, PTM Grille Surround, 35% Front Window Tint