And more.....

If your going to repower it and get away from what you have a single big block is worth thinking about. Personally I would make every attempt to keep it as is except for a counter lower unit and props. If you change to either twin small blocks or single big block you will need to fill and recut transom and reconfigure stringers. Good luck deciphering everyones opinions. I have added your boat to my hope to find list.
Jim