Dick -- Until recently I've always had an original Continental 185/HR14 spare in the trunk. That's all I've ever had, and as might be expected with that original tire there was no observable contact with the trunk hinge.
Funny thing about that original Continental spare though. Not long after having bought the car (20 years ago) I noticed the spare didn't have air. I asked my local service people to take care of it. They said they did. Then maybe a year or two later I again noticed it had no air. After going through this slow leak-down problem multiple times I finally insisted they put a tube in it. They did NOT want to do that, but I held my ground, and when I picked the car up the bill reflected the cost of a new tube. The spare wasn't checked for years afterward, but more recently I noticed once again that the spare was flat. Then I finally saw that the old original Continental says right on the sidewall "Tube Type". I don't think the service people ever paid attention to that, and it was clear they simply did not want to put a tube in the tire. It also recently became clear that they'd never put a tube in, and that they'd lied when they said they did. The result was that I'd been driving around for the better part of 2 decades with a flat spare that was taking up a lot of trunk space.
As mentioned earlier, my interior guy will soon be redoing the trunk. And like a new SL my 280 will no longer carry a spare tire, but will instead have a nice little storage compartment built in for a can of "Flat Fix" along a small 12VDC compressor.
Tom in Boise