Here is a quick and dirty OL30 install on my KTM 520.
I just used some holes that were already in the rear fender and had the bags roughly installed within 1/2 hour.
I will need to finalize Rack Loop locations and find a better spot for the lower right ladder strap as it is too close to the exhaust. I think I will put a hole in my exhaust guard for the ladder strap to feed through.
When riding the 520, I use much more of the rear portion of the seat than on my 640.
The install of the bags on the 520 is much farther back. You might be able to move the bags another couple of inches back, but I wanted them to stay on the number plates.
Hope this helps with your decision.