If I might return briefly to the Hell Gate Bridge, I grew up in Sydney, Australia and was familiar with the Sydney Harbour Bridge:
This was completed in 1932 after a long period of planning and construction.
Early designs were of a cantilever design, and John Bradfield, the project leader built such a bridge in 1940 in Brisbane:
But after the completion of the Hell Gate Bridge, an arch design was adopted. The Sydney bridge is virtually the Hell Gate scaled up by 1.6 times (span 1650 ft) although the deck is even wider with provision for four tracks and six road lanes. In the 1960s, two tracks used for streetcars were replaced by two more road lanes.
One structural difference is that the Sydney bridge uses pin joints at the arch supports on the piers while the Hell Gate has rigid supports.
I actually have a photo from the top of the World Trade Center showing the Hell Gate Bridge in the distance, taken in 1990.
I never realised that Rocky and Bullwinkle shows were in colour. Colour TV arrived in Australia in 1975, and I don't think the shows were still broadcast then, nor would I have watched it, I guess...