I don't think I've ever seen one around, but it is fairly easy to do it. There's a handle below the bottom right corner of the MPU. Pull up on the handle will release and pull the mpu up about 1/4 inch, once you see this happen, you can just pull the mpu out of the hinges that hold it in place. You must remove the mpu door (if there is one) before you remove it. The mpu door is removed by opening it and then sliding it to the right.
To re-install, do the opposite. Live up the mpu with hinges on the back, push down on it, and the secure it by pulling down on the handle. Then install door.