The best advice I've seen so far is to just cull every cane/branch outside the main stem except vines running on the structure. It would be a year without fruit, but it puts me into a great position for the future.
Not sure if I should just eyeball dead vs live canes during the winter or just cull them all
Here's a video from some experts in California:
https://youtu.be/UShiwymsX0w