My car, when I bought it 20 years ago, has a lot of keys I never questioned until I got my '70 280SE. I have the large key for the ignition, another key for the doors, one for trunk and glove box, and one for the gas cap. On my SE, the ignition does the door, glove box and lock. The size of the key for my SL does not look like that was the same approach, although who knows who changed what over the years. Was there a difference between the 230, 250, and 280 over the production run?