In the latest episode of The Kindle Chronicles podcast, this very topic is addressed. (Though not much time is dedicated to it.)
The Kindle Chronicles Ep. 133
One person came up with a solution I had been thinking about myself...velcro. Velcro certainly works for Oberon covers; why not the Amazon cover as well?
The submitter to the podcast said he used a hacksaw...I was thinking tin snips and a file, but whatever works sounds great to me.