This is one of the earliest photos of Point Dume on record, dated 1898, and shot when the Rindge family still owned the entire 13,3000-acre Malibu Rancho. The photo was taken on the bluff overlooking Big Dume Cove, also known as Pirate's Cove, and it documents the unaltered, unflattened top of the hill on the Point. Source: The Malibu Post
The style began in 1959 and ended in 1962 so for me as a group I see them all as bubble tops regardless of glass area. As body shapes changed the roofs were altered in area to accommodate the new body styles culminating in the 1962 which is the most pleasing roof of the group. I wonder if the glass was shared with progressing years, say 1959 to 1961. Like you pointed out it is a matter of opinion. Thanks for all the info.