Malcolm
Thanks for posting these
The course has been altered somewhat since Colt finished it in 1931 (it was a new course not a redo). From what I can work out the changes were driven by a new road (outward 9) and wanting a large practice ground in the center of the inward 9.
Some nice green shaping!
1) Original
2) Original
3) New hole. I think you can tell here, the green shaping looks wrong.
4) New hole. The green fits better here.
5) The green is original but it played as a medium par 4. Green was not closer to the cliff.
6-13) All original. Except 13 is now narrower and has OB everywhere because of practice ground.
14) New hole. Green looks a bit different here.
15) Maybe original but I think green is new and a bit farther on.
16-18) All original
Off the lost holes I wonder if the original 3rd is still visible? It played from the current par 3 tee but was a par 3 in the opposite direction to the current 5th. The green was approximately in the same area as the 6th tees.
Bunkers were much larger/rugged originally. I have a nice vintage pic and will post.