...Larry has it right! The later models mount with sheet metal screws, But in the case of My '74, there are small 'Metal Clips' that slide over the edge of the Sheetmetal; over the Holes, that the Screws Screw into. So with those clips (found at any auto supply house) there would be NO problems converting from the 'Stud' design to the Screw Mount. I don't like the clips, Myself, I have thought of installing 'NutSerts'; as a More 'Solid' Mount, and I could then use Stainless Steel 'Machine' Screws. One good thing about the Clips...If one should 'Strip-Out', just pry it off and slide on a New one! Keep watching 'Ebay Motors' (Pantera), Those Grills come up for Auction every-so-often. Good-Luck with it!...