Animeka, is cutting your machine an option for you? If so, I would go with severedhed's approach, if not, you are going to have space issues, and will have to do either a tiered approach like kremmit suggested. I once tried to make a deluxe control panel on a 4 player cabinet, and there wasn't enough room. (I wanted a 3 inch trackball though). I'm going with swappable control panels now. You may just want to make a control panel that just spills over and you just need to be careful about weight distribution (make sure that you will not put pressure too close to the front of the control panel). With some effort and thought though, you cold probably do something like this without cutting into your cab.