I used this one https://www.amazon.com/dp/B013DQ4ADK?tag=wranglerorg-20. I ended up extending it to a more comfortable position simply with a piece of 1/8" flat steel and drilled some holes for adjustability. Mounted it to using the same bolts as the door limiting strap and it has worked perfectly. Very happy with it.
I have this one,it was like 50.00 when I bought it,I use it more than one would think.without it my leg seems to keep going,tjs do have ample room to stretch the legs out.