Having extra or missing holes, grooves, humps, flanges or whatever is not uncommon in the world of cost driven manufacturing. The bean counters want "one part fits all" to be the mantra so they don't have to pay for expensive tooling. The question whether your panel's hump is "correct" for your vehicle is likely an answer you'll never find a definitive answer to. The world of reproduction and even OEM parts having "features" that aren't a perfect match to the original has existed for a LONG time. Looking for the "correct" part is rewarding if you're lucky enough to find one, confounding and frustrating if not. In the world of 50-100 year old cars having to make due with something close is just a fact of life. Don't dwell on humps or this or that. It's possible the manufacturer of that part put it there on purpose so they could sell it as a part to fit several different vehicles, some assembly required.
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