Hmm. Really, i don't think removal is plausible; a jeweler or fine metal worker could probably polish down past the engraving, but it would change the appearance of the metal, to properly do this you'd need to remove all of the engravings, then reapply the name, apple logo, and text at bottom. which is too much work. as far as ordering a replacement plate, i don't think this is an option either... as the backplate includes the serial number, it's not going to be a stock part. you might be able to find one on ebay or somewhere, if you can live with an incorrect serial number.
paul