Was planning on doing that trip this summer, but things have changed and will be doing it by car around the same time your going as I work my west to drop my sister of a university in BC.
Are you camping? Hotels?
If your not camping you can pack really light. Rain gear is important, and make sure your rain gear actually works. I like to keep a tool roll and a tire repair kit if something happens you can at least limp to somewhere to get it fixed. Other then that, just enjoy what happens.
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