Wow, man........you need to get off the inner webs long enough to do some actual research on this!!
Can't believe it's a question. You can look at any car dealer or truck in any parking lot you see to see the size difference!
Neighbor, buddy, guy at the gas station at the pump next to you have a pickup? Hard to believe you've never seen/noticed that crew cab back seats are about 2x as big as ext cab.
Thought at one point you wanted to use the back seat as a remote mobile office. Maybe that was last week's wish, lol
You said you're short, but unless you're midgets, that won't work in an ext cab back seat.