The Camper Special that started in ‘65 is not the Super Camper Special.
The Super Camper Special was made throughout the ‘73 - ‘79 Ford bodystyle run.
It was essentially the longer wheelbase cab & chassis with an 8’ pickup bed modified to fit.
They didn’t fade away because they were too long-wheelbase and hard to drive (because they really weren’t) they faded away because in 1980 Ford started selling regular, extra, and crewcab one ton dually pickups that worked great for camper hauling. The old Super Camper Special required a bunch of expensive special tooling... different bed sides, different inside of truck box, for relatively few sales. There’s also the issue of the inside of the box being non-standard which meant many things didn’t fit it, including some campers. There’s less space inside the box behind the wheelwell and camper rear corner bathrooms were starting to use that space. It kind of sucked when your camper wouldn’t fit if you bought a Super Camper Special!
Trucks with bigger cabs - which were getting a whole lot more popular - already had even longer wheelbases. They really didn’t need the rear axle pushed further back.
It just no longer made sense to keep making them.
At the time, it would have been the reigning king of camper haulers IF Chevy hadn’t started offering the Crew Cab Dually at the exact same time, 1973.
Chevy pretty much owned the race car trailer, horse trailer, and big camper market for a long time because of that.
Those “square body” Chevy crew cab duallys were amazing, excellent trucks, relatively unchanged all the way up to 1991. I had several and still have my ‘86 model. I just can’t sell it, it works too well and it’s just too reliable.
Those trucks haul 11.5 campers with ZERO suspension mods, sit level, handle great, drive great, and are super reliable due to their simplicity.
Only problem is unless you do a Cummins swap, they use fuel like mad!
Actually Chevy was the first to start offering a diesel in the early ‘80s, the 6.2, which is NOT the converted gas Olds a lot of people assume. It was a good engine and got great mileage but had no power. I had one and ended up yanking it out and putting in a Cadillac 500 so I could ever get moving from a stop on a hill. I had the same problem with an early Ford 6.9/automatic. Would not start moving uphill from a stop with a trailer on.
Ford had to start offering their own excellent version of the Crew Cab dually.
That’s what killed off the Super Camper Special.