If I look at my own analysis of the SST, then 76-77 was a strong La Niña year, the warm blob was a bit farther south than in 2014. I was in Colorado that winter and there was not much snow in the Front Range. Fig. 9a of Miyakoda and Rosati (1984) shows a warm blob at about 35-40N and 150W, about where you expect warm SST associated with La Niña, and a cold anomaly exists to the north along the coast of Alaksa. The warm blob in 2014 and the NPM warm blob are a bit farther north and the warm SST anomaly extends all the way to the coast of Alaska. These subtle variations in positioning are what the two decadal modes pick up as leftovers from the ENSO mode.