Athanatos

so i wanted to do a conversion of my sealed beams to a composite style headlamp and my endeavor was to change my whole front end (radiator supports/grills and all the lights) but it looks like they make a sealed beam conversions

now my issue is the measuring of the lenses are they measured from the glass itself or the outer flange when they attach to the vehicle cause i could be stuck either to buy a 7x5 or 7x6