IU always hated having to shove the 30amp cord into the box, and sometimes it was hard to get it all the way out, so I cut it off and made a 3 foot pigtail which is all I have to push in and pull back out.
The unused space in the box where the power cord used to live happens to be between our two recliners so I made it into a book/magazine shelf. I put a replacement male plug end on the pigtail, and a replacement female end on the power cord that I cut off. The power cord stores in my storage compartment along with the 2 other 50 foot 30 amp extensions I have. It doesn't matter which one plugs into the pigtail, because they are all the same. It's cheaper than the Marinco detachable setup, and the best part is I won't leave home and forget the screw on cord for a Marinco Adapter. Any 30 amp extension will do. All my cords live in the storage compartment.
As for mice, etc., I just keep a stainless steel pot scrubber under the power cord door and wrap it around the base of the pigtail when it's extended and close the hatch.