I have a Thule luggage rack and top carrier which I have carried from car to car over the years. I purchased the 500x (Trekking Plus) and Thule says "there is no safe solution for a luggage rack on this car." We checked (online) via Fiat and elsewhere and can't even find Fiat options - presumably because of the glass roof. Has anyone tried to find a "safe" solution using just the frame? Any ideas?