I was at the Legends of the Autobahn show at Monterey this past Friday (14 Aug 2015). The Classic Center was displaying a car for a customer. A gorgeous deep red/brown 230 SL. I was not judging this particular class and asked Michael Kunz about the hood bumpers on the engine bay firewall flange. This car had four, and I was under the impression there were always three (to coincide with the three "buttresses" on the hood). He scratched his head a bit, and we went on to our separate duties. A little later he called me over and showed me the engine bay picture from the 230 SL brochure which clearly showed four bumpers. I have this brochure, both the horizontal and vertical format, and that is where the picture is from. The horizontal (landscape) format brochure is dated 863. Was this an early prototype? Were the early cars delivered this way?
I did look at 49er's engine photo and while you can't see all three, there is one bumper centered on the central heed latch.
Picture from brochure attached