What you're talking about is the ball mount, and most all ball mounts have a rise and a drop, and are made to go both ways. What you want is for your egg to be level when attached. So yes, go for it. I've been reversing ball mounts to keep a towed trailer level for years. Just make sure everything is good and tight, check it once in a while, and don't forget the hitch pin for the ball mount!
By the way, I always change the orientation of these right in my hitch, with it pinned. It's the easiest way to do it, and you don't have to go far. It helps to by a big wrench sized to the nut on your ball too.
2012 ParkLiner #006
2013 4wd Escape 2L Ecoboost with 3500# tow package
2001 F-150 XLT 4wd Super Cab 4.6L