You know what part of a car gets dirty the fastest? The back end. Right where you put a hitch mount rack and bike.
We run a Subaru Outback and a Tandem Topper.
Agree that having the tandem bars locked into the straight ahead position is one key. I have a rope that I tie to the bars and captains seatpost for this.
Next the Subaru is high/tall enough that pedals have to be in just the right position so crank can go into door opening.
Still a bit of a chore to get back end up high enough to get into trough.
Another key is mounting the rack as far to the outside as possible. We are using the factory rack crossbars so we are somewhat limited there.