My old CJ5 had the same issue with the rod assembly popping out of the clutch fork, I adjusted it a few times and the third time I said screw it and bought all new components. What a world of difference that made, nice firm pedal every time and never had an issue again.
I even went ahead and replaced the brackets and pivots on the frame and trans, everything new and didn't have to worry about any thing being worn. Plus I knew how everything went together and how it worked so I had more confidence in the set-up.
I found out about Jeeps late in life, so now I have to play catch up and get as many as I can. Man, life is great