Those are cool motors. I had one many years ago on a tri-hull. Hauled butt. Lots of Merc racing technology from the Kiekhaefer days left in them.
Back in the mid 80's I had the privilege of working at Mercury's "Lake X" , a secretive research facility somewhere near Kissimmee Florida. I forget exactly where the lake was but we stayed in Kissimmee. Nobody was allowed in this place but the people that worked there and even they were vetted for spies. I was involved with a new ChrisCat (catamaran) offshore team. It was a joint effort between Chris Craft and Mercury and we had carte blanche at the facilty. We spent about a week down there testing and sorting out the boat. That place was really neat, it was built in the 60's but the buildings were futuristic looking like something out of Disneyland. They had a long dock out back with a dozen or so outboard motors fixed to it and they would let them run around the clock. There were gators in that lake it used to give me the creeps just standing out there. I remember armadillos running across the roads in there too when we were trailering in. I was like "what the hell is that thing ?"
Anyway one day they let us upstairs in one of the buildings and there was a museum they had built there dedicated to Kiekhaefer..all kinds of cool stuff from early outboards to Nascar stuff to big injected Chevy motors and marine accessories. I think there was even some kind of air cooled radial airplane engine on a stand.
I think Lake "X" is gone...the environmental zealots probably took it over. I wonder what happened to all that stuff they had there.