42 45 81 96 185 197 503 | The relationship with the Golden Gate Bridge & San Francisc-Oakland Bay Bridge +The February 11, 1968 U.S. Navy boat crash

Construction on the Golden Gate Bridge began January 5, 1933, a span of 185-days earlier.
Mathematics = 185

The bridge opened a span of 197-days before the Golden Gate Bridge, May 27, 1937
197, the 45th prime; Bridge = 45; Golden Gate = 45 / 45

https://en.wikipedia.org/wiki/San_Francisco%E2%80%93Oakland_Bay_Bridge

Notice this incident happened on the 42nd day of the year, February 11.
Freemason = 42 / 96; San Francisco-Oakland Bay Bridge = 503 (96th prime)

It was also a date with 81 numerology. 
2/11/68 = 2+11+68 = 81; Golden Gate Bridge = 81 / 81

Notice the Bay Bridge is 81-years-old at the moment, coming up on 82.