Everything works but it needs a good clean. I have removed the two small top covers, exposing the power take-off and the long top cover that extends the full length of the machine. Despite removing 2 Allen screws on the underside, although it is now looser, I cannot slide it sufficiently to lift it off and suspect there is a hidden catch or screw somewhere. I don't want to force it and break it, so would like to buy or download a Service manual for this model.