Just cut the all Four Borders take the elastic under the slim drive and put on your benq drive, fit your dirve with care in you xbox s, and use Glue Hot to fit your Faceplate of slim drive on your benq and all is done. Use the power cord of your benq drive because cord of slim is a litle small.
dont do that man.... just swap the tray, they're indentical.
take a look on this link, it is in portuguese, but you can see the pics and try to reproduce!!!
http://forum.outerspace.terra.com.br/showthread.php?t=320078