I have an "unofficial" handicap where where my inseam is only a smidge above 22 inches. It gives me all sorts of problems from finding pants to procuring furniture.
I manage to drive a 6-speed.
I have no Idea what's up, but it seems that with every new generation of Jeep, the pedals get farther away. My TJ only needed a small bit of an extension, I needed a full inch more in the JK. I was able to drive a friend's YJ renegade without any extensions.
This is what I ended up doing in my 2013 JK with some scrap wood:
(excuse all the salt stains, I live in eastern Ontario)
If you're willing to drill a hole or two into the pedal, it makes it a lot easier to come up with a solid way to build extensions.
I also put some foam boards under the floor mat so I can rest the bottom of my feet. Nothing is more jarring than a floating foot on the gas in 1st gear over bumps.