I've recently learned that the MMM and BH can not be installed at the same time on the CK20. To install one or the other you need to move some mounting plates/brackets (?) around and that takes quite a while. You didn't mention BH in your post so maybe this would not be a problem for you.
Fred
P.S. I laughed long and hard after reading wallace's signature /forums/images/graemlins/grin.gif