I second the motion to screw the joys in from the bottom of the CP. I did mine that way and haven't had any problems. Alot of people on here disagree with this type of mounting, but there are those of us who've had great success doing it this way. I think its all about drilling a pilot hole and using large thread screws. I personally used of all things Metal screws(not to be confused with machine thread screws). #12 x 3/4" hex washer head zinc screws to exact. These are quite beefy and have held quite well for me. I feel certain that the joystick base will break before one of these lets loose. Of course, you'll most likely feel the need to route a recess if you mount the joys from the bottom. Otherwise the joys will be rather stuby in height. Some people don't mind, i think most like a little extra height. I routed close to a 1/4" recesss for mine i believe. So far i've been quite happy with the way its worked out. Just my 2 cents.
-Kevin