- Disconnect all cables from the unit, including the power cord. Remove the screws which secure the Edit Pack top cover to the chassis.- Prop or hold the cover up slightly, and place a piece of thin cardboard between the cover edges and the Meter Bridge lexan. (This protects the lexan from being scratched by the edges of the cover.)- Prop the cover up high enough so you can gain access to the trackball.- Remove the two screws which hold the trackball in place while supporting the trackball from the inside of the unit.- Unplug the cable header that is plugged into the trackball, noting polarity for reinstallation. - Turn the trackball upside down so that you are looking at the bottom of the printed circuit board.- Remove the 4 screws which are located closest to the ball. They form a diamond shape. - The parts likely to accumulate debris are the 3 stainless steel rollers. Clean these 3 parts with isopropyl alcohol and a lint free swab or cloth. - Wipe down the ball with a lint free cloth- Reassemble the trackball.- Attach the cable header to the trackball assembly.- Install the trackball into the Edit Pack top cover.- Lower the cover, remove the protective cardboard, and reinstall the screws.