For sure you want to drill all the holes (and close unneeded holes) before paint. Like I said earlier, I think the plastic ones are more forgiving when you don't have factory holes. Sources for emblems - Layson's Restorations (they have a vendor link here), Year one, Classic industries should have the Swinger and Dart emblems and the cursive Dodge for your hood and even the gold pentastar for the bottom of one front fender. Sometimes the emblems come with the plastic barrel clips. I'd get some new clips, put them on an old emblem and do some test fitting on a scrap piece of sheet metal. The plastic ones should slide, with no resistance into the hole until you get to the swell at the end (see earlier poster's picture).
