amazon sells a A-pillar hood bracket that's marketed as a "ditch light bracket" and fastened to the Tahoe-suburban-yukon via the hood-hinge arm bolts (underneath the hood) and only contacts the underside of the hood. bracket hole is prolly the correct size for your antenna mount, or hole can be drilled a little larger.
Amazon sells another variety of bracket that's similar in performance but it fastens via 4 bolts that "clamp" on the hood's lip itself,, but this style makes me nervous that it could bend or compromise the paint on the hood.
both styles will pop up on amazon when searching for ditch lights and brackets
The first style I mentioned will be better for RF grounding as the metal bracket comes into direct contact with the metal hood, whereas the lip-clamp style has a rubber protector gasket that stops metal on metal.. so not a good RF ground that antenna needs for ground plane.