since I have this dead 24x drive and some more thin plexi. maybe I will try to do this. If I manage to pull it off, I will do a guide for it. The only way I can think of off the top of my head using the bend method is to create a form representing the inside dimensions of the drive casing.. I already have a form representing the dimensions of a CDRom drive, all I would have to do is trim it up a bit.. As Linear said earlier, the hang up maybe the thickness of the plexi... could throw off the dimensions of the box and make it hard to mount... /me goes off and thinks..
Is there any reason that you bent it upwards and not down? Would it be easier/better to heat up the acrylic and let gravity pull it down slightly, then start flattening it against the side of the drive?