Hi Mike &amp; Chris, I just got on here, and saw your posts. 
I too, have a 1955 Super 55, and they're my favorite Olivers. 
Mike, I couldn't help but notice that your S/N is very close to mine.... Do you know the history of it, or where it came from?  I bought mine about a year ago in the Fife area, but I'm told that it came from the Yakima area originally. Anyway, my S/N is 13,142... 
I live just West of Port Angeles in an area called Eden Valley near the Elwha River, not far from Lake Crescent. 
As far as the talk I've heard of fuel caps protruding through the hood, I've never heard of this, up to now. Mine looks as yours does in the picture, with the cover over fuel and radiator cap. All of the ones that I've seen look like mine and yours.... It makes me wonder, as I've seen comments when looking for parts relating to hood opening to left or right, or from left or right, and thought that sounded odd. 
Does anyone have a close-up picture of this? 
Thanks!
Patrick