I took a piece of galvanized steel flat stock and bent some tabs on the ends and fastened it to the frame. I drilled some holes in the frame and tapped it to fit some 10-24 screws. That hold one side and the other I just drilled a hole in the round frame tube. Worked out real well. So far so good and with the fan and heat shield I put under the seat it is notisibly cooler in the side area which is what I needed for my boy riding shotgun all the time.
Hope this helps.