My longest carry was from mile 620 (Willow Springs) to Walker Pass at around mile 651, and I broke that up with a dry camp at Bird Spring Pass. It really wasn't too bad since I had little food weight at that time and was heading into town for resupply. In general, it is a GOOD thing to be very conservative and careful! I was pleasantly surprised by the number of water sources that were good vs. what I had assumed. It really is not that bad at all.
Here is the "well" at Willow Springs where I scooped about 6L of water:
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