I have a GS with the Touratech Zega Pro luggage racks. Here's my setup that might give you some ideas.
The bags are larger than the frames, so frames offer good support and work well with the D-rings that are to be used with non-Wolfman racks. However, my concern was for the possibility of the exhaust pipe burning a hole in the Wolfman's in the event of a tip over. So I had an ADV forum member (TwinHeadlightErnie) make me a couple of backing plates out of aluminum and powdercoated. I decided to get one backing plate per side for each side as it provides protection for the Wolfman bags. The backing plate is not load bearing so it is fastened to the rack with tie wraps.
Here are some pictures:
Picture of the backing plate installed:
Top view of space between muffler and backing plate:
Bike with bags installed (the astute viewer will notice that I did not install the D-rings correctly, but this was just a trial):