I'll add that we haven't taken the doors off of the JK, only the TJ and I cannot say with 100% confidence that these same pegs will work the same on the JK hinges.
The square corner on the peg mount stops them from flipping forward on the TJ because they stop against the hinge plate.
I'm not sure if the JK hinge plates will catch this corner the same way.
All that was needed to install them was a pair of nuts & bolts that fit the diameter and length.
I think they are 3/8" x 2.5".
I used fine thread bolts and nuts w/ the nylon inserts so they wouldn't easily loosen up on their own.