It may show my age, but I remember when cars had a single 7” round sealed beam headlamp on each side (and only one tail/brake light on the rear and the turn signal was your arm out the door). It didn’t matter the make or model, they all used either a 6v or 12v version of that bulb. Then they went to the pair of 5” round, one high and one low beam on each side. Then the rectangular ones came out. All in all, they were cheap and easy to replace and aim. Skip ahead several years and we have nearly one of a kind lights on all corners. They are different for years, makes, models and trim levels. As a vehicle ages, it may be harder and more expensive to source these nearly one-of parts. No wonder our collision insurance gets higher and higher.