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hello, i need the same project but with a little modification, as in the picture (http://www.hostingpics.net/viewer.php?id=290676Capturedecran20140205a144922previewfeatured.jpg), I need two holes at the bottom (2) for secure with two screws, and I don't need the part (1) for fingers and hand part, i need it smooth. please help me to edit the file, i dont know how use sketchup to modify the file. thank you.