Bike rack that will fit Roadtrek with Continental Spare Tire

I have a Roadtrek 210 Popular with a 2" hitch receiver. I have been researching bike racks. (Our current fold-down platform rack is no longer suitable.) I want a lighter, vertical-style hitch rack. I am looking at the Swagman 1,2, or 3 bike rack (64152-2), which comes with a 14" hitch bar, still too short to clear the spare tire. It's been suggested to me that all I'd need is a Curt 8" hitch bar extender for 2" receivers. Does anyone have experience with this particular configuration?