Thanks. I have some later 70s pot metal grills that are not exactly square (5.375" right to left, 4" front to back at edge towards A pillar and 4.378" front to back at edge towards center speaker, studs are 4" right to left, centered front to back). These may cover the speaker holes if I convert my dash to 3-speaker when I get it redone. I want to be able to replace the later 70s grills with originals if I can come up with a pair.