There was a green 8 that parked his RV next to me in Hot Springs that had a neat bracket that I thought he said was made by Mountain Man. It basically had the base butted against the angle at the back of the bed and then had a neat locking bracket that held the top of the jack to the angled part of the rollbar. Opps, Jeep calls them Sport bars.
I have done an internet search for Mountain Man and no luck. I remember seeing that brand of accessories but no luck.