I found an ultra cheap and effective way to add mirrors when the doors are off.
This is for the 2007 Jeep JK's only.
First, find your AirConditioning vent. (Notice windows in the distance are an AutoZone Parts, This can be accomplished in the parking lot)
Next, turn it closed so the flat/solid side faces you.
Third, Take the small round mirror you just purchased in AutoZone and line it up to make sure it is slightly smaller than the vent,
Fourth, remove the back piece of paper that reveals the sticky surface of the foam tape which is on the mirror and stick it in place.
And add another to the passengers side if desired and adjust for best view
This mirror can be rotated out of view to use the Air duct as usual.
Cost = $1.99 ea.
This has been "Mike's Mirror Mod" tell everyone about it!