1970 Dart Hood scoop and pin hole sizes

I have bought a used hood for my 340 swinger and now have to install the hood scoops and hood pin holes. I want to drill all of the holes before it gets blasted and painted. Could someone tell me what the proper hole sizes are for the scoop holes and the hood pin holes? Someone told me one of the scoop holes is oval, is that correct?
Also, for drilling the pin holes is it best to try and fit the hood first and then mark it or drill through the centre of the locations on the hood underside?