This is my setup. It uses a ball I have never seen before that came on my 149. There is a hole thru the center of the ball and it attaches with a 1/2" carriage bolt. I bought a longer bolt and used it to attach the hitch to the sleeve hitch adapter. Hopefully the picture makes more sense than what I typed.
I have flipped it over for better tounge clearance when using the ball hitch.