Thanks for the comments everyone!
I wanted the ball to rotate freely on the legs so that the ball could rotate without having the legs turn the whole system around but I am having a hard time fitting the ball to the legs. I don't have anything in my spares box that will attach the two different companies parts together. I will probably have to scratch build something.
Bandai does make a Polypod kit with the mech legs included but the Polypod kit is pretty expensive and the ball still doesn't rotate freely. The Bandai Gundam Ball and the KOTOBUKIYA HEXAGEAR kits I got were a lot cheaper than getting the Polypod kit by itself. This is why I went with getting the Gundam Ball and Hexagear kits. Even with the Tamiya 20mm Flak and metal barrels, all together it was still cheaper than getting the Polypod kit. I got my Bandai 1/35 M61A5 MBT cheaper than the Polypod kit.
Here is the Polypod kit I was looking at but it is just not affordable at this time.