My folks have a '67 but with an outboard, this is the first one I've ever seen that had a jet.  They are not very common boats even in outboard set up so it's definitley unique.  Is it a full stringer? How long is it?  Ours is a 16' and it always gets sketchy with 4 people in it, sits REAL low in the water but other than that my folks love that thing.  They say it's been one of the best boats to ski behind.

"Stringers" are the (generally 2"by6" wood) boards in which your motor plates would mount and they support the engine and add strength to the hull bottom.  They are usually from transom to just passed the engine or they can run almost up to the bow.

I would almost like to guess that this boat would have 1/4 stringers(they run from transom to just passed the engine).  The shorter stringer would limit the amount power you would want to put into it and you would probably see a bit more flex out of this hull in rough water conditions.  We only run ours on the lower river in glass water or in the off season anywhere else due to how low it sits in the water.