Hi there, if you are still asking?
I'm new here too, I joined to follow some builds and don't normally post, but spotted your lonely post and picked up.
I have build many boats of all types over the years. I restore old sailing yachts, really old yachts like over 100 years old and get them back on the water.
I have never seen such a boat as you have posted images of.
I thought at first it was a 'straight runner' but this has a rudder that can be controlled?
The forward compartment looks like it held batteries of some type, the wiring looks like that used in the 1930's in UK, (I'm Isle of Man), but the motor mount and position plus tanks and tubes would suggest a "Diesel" engine, like a petrol based fly boy engine. Those tanks and fuel pipes are not for electric.
There are also switches up front as well. Very curious find indeed. Sorry you are so far away I'd love to have a route about inside it.
Have fun, a full conversion to electric would be simple, an ESC and motor and a single servo to operate the rudder would have the boat running again.
Aye, Kim