Re: Need help figuring out allot about this boat!!!
Looked at your pictures - the hull looks in good shape other then the transom cut and the sawzall hack in the gunwale / hull cap.
As far as the transom cut, for a "normal" motor, you would have to repair it. I used 2x10 pressure treated in mine, and brought the height of the transom up to the bottom of the hull cap.
I cut out a narrow area the width of the motor bracket to mount the motor for the correct height in the water. Angled cuts, round cuts, whatever. The mass of the transom material is where it derives its strength, not its shape, however. Mine is cut at about 9-degrees (fairly sharp) and it has been that way since 2001 or so with no issues whatsoever.
Often you will find a hull ID plate with serial numbers on the port side of the transom from inside the boat. You surely have a Niagara... Looks identical to my '64 right down to the wires in the prow area. (photo 9)
The hardware for the top bows do not appear to be "factory" (photo 12) and the "Custom" had a splash well - probably removed when the transom was cut.
I guess you need to decide your priorities. You could probably buy a complete boat for what you will spend refitting this one and fixing the dumb stuff like that sawzall cut. And you still will need a windshield and steering components. If you are boudn to "restore" this one, it will cost more than just buying one complete FWIW.
Good luck!