the Russian PT boat... was built with a tank turret. Think about that, mighty top heavy, but well armored and eliminates a lot of design time

They just found one, and pulled it up, from the Volga River near Stalingrad, and clearly it had been in a lot of fighting, and they were quickly stopping leaks by pounding in wood cones. Some pretty big hole must have sunk it though

https://dailytimewaster.blogspot.com/2017/12/russian-wwii-pt-boat-recovered-from.html