It seems unlikely because it's much easier to drain the manifolds on most V6s and V8s than the block drains. After my first experience with winterizing mine years ago, I totally re-configured the back of the boat to make the seats easy to remove and the wood framework that supports the big sun pad. I'd prefer 2 jump seats and a dog house, but at this point I don't feel like putting in the work to do the conversion and make it look good. Modern I/O boats are just maintenance nightmares. The designers should hang their head in shame. When I go to the Nassau County Boat show (Long Island NY) there are hardly any I/Os on display, there used to be a lot. Very few people here want them, for all the reasons we know well. I used to get a kick of asking the salesman "hey where's the starter on this one?" knowing full well it was buried and if you don't have to pull the engine you're lucky!
I/Os made sense when engine compartments were wide open, had easily removable seats/wood supports and the engines were simple carbed GM inboards, and outboards were noisy & smoky!