Douglas, what appears a reddish brown wood on the deck , was that mahogany??
The decks were teak, which is a silvery light tan color. It's endures in a wet environment better than any other wood.
Do you refer to the reddish brown color of the deck cabins, hatches, etc.? Naturally we don't have color photos from those days but using examples of yachts from that era that still exist, I would say that yes, it is Philippine mahogany.
The mahogany used today comes mostly from Honduras and is more open grained.