Why strip the DRM anyway? It seems like Amazon is playing fair with us. You and your wife can both read your books as it is. Amazon keeps a library of the books you buy so you don't need backups. Amazon is not like some other online retailers (whose name I shall not mention to avoid flaming) that trash your purchased content when they send you an iOS upgrade, even if you always played their tune, and refuse to let you re-download your old stuff from their site.
Amazon keeps track of what you've bought and if you wipe it out you can download it again. You can de-authorize devices and authorize a new device--cell phone or Kindle, PC or whatever--and download old books you want to re-read on the new technology.
Personally, I can't think of a reason to strip DRM from Kindle books.