Piece of 1x7x.120(1/8") bar
Throw it in the forge/over the firepit(on a grill)/over the oxy/acc till it is red hot
Take it over to the vise and bend
Heat again then bend again
Boom you have your bend
Now drill your holes and make the finish cuts
Slide some rubber inside some thin wall tubing and fit it onto the radiator placing the bracket on top and maintaining proper spacing.
Tack it once your happy with the fit then finish weld.
Paint.
For a finished look that will be lighter you can take the thing to someone with a 3d printer and they can print one off within a day. My cheap butt still does not have a 3d printer yet. But this is one part I would make on one. Still use the rubber of course as isolation. But you will be able to have webbing and gussets as well as adding a logo or something as this highly viewed area using 3d printing.