This is a futile search. Even if you found one, it would be totally worthless.
First: Even if the
builder had drawings, over a 5 or 6 year production run things change, and few builders were good about keeping such records.
Second: The youngest of these
boats is 40 years old. You have to assume that NOTHING is as it left the factory. Assume EVERYTHING has been modified by a previous owner.
If you are going to do your own
work on an old
boat like this, the first thhing you have to do is make trace wires and hoses and draw your own schematic, and then modify it as you make you own changes.