Why don't you remove it or fold it up flat (as possible)? When I take long trips, the back is usually so full I can't use my inside mirror, so I just use the outside mirrors. Same when I'm driving a box van. There's an inside mirror, but it can't see through the box.
As always, YMMV.
Daren
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2008 T4R Limited 4WD V8 | Stock Rims | Michelin 270/70-18 LTX M/S 2
2004 Greyhound | 25 Races - 3 Wins | 0-45 MPH in 3 seconds | 45 MPH - Couch in 2.5 seconds | Retired in 2007