[BenchZowner]

And remove any stickers prior to washing it up, because they might change color, or partially or totally get washed out and leave you with blank stickers and no serial number :p

To remove any kind of sticker, including the warranty pre-cut pattern ones, heat them up with a heat gun or a hair dryer until they're very hot to the touch, and progressively yet slowly remove them.
The same applies for placing them back on, heat them up, stick them, and heat them up more, and let them cool down.