I had the exact same issue as you did with my tunnel bending in the middle so I ended up making a 1/4 thick aluminum plate that fits over the rear tunnel section and overhangs a bit. It is large enough on my 137 to accommodate two link q bracket sets back to back and I can now use the medium link q bag on the far back, the stackable fuel can on the front and even stack a second bag on top of that. I powdercoated it black and even had room to install two octane boost cans directly behind the seat in the void where the small factory bag sat. It all works real well and was easy to fab