Before going through the trouble of changing these sockets, I followed surprisinguy's advice to check the polarity to the sockets first. Mine were fine, so I decided to scrape the connection points inside the sockets and pry them out a bit to ensure solid connections to the new bulbs.Please keep us updated on how well this strategy works.
That worked. My new 2357 Zevo LEDs now light up fine, although they do hyper-blink when I use the turn signals. I'm installing a load equalizer on each socket tonight to deal with that and everything should be good to go.