I'm curious if any sort of detailed map would exist at all. My understanding is the CA-190 crossing through the Sierra was more or less just a line on paper and nothing more. The traversable segment today is realistically the only thing that would ever become a CA-190 segment. I stated before the last time I drove through that portion of the Sierra, around October or so, the roadway was in pretty good condition. Except around Kennedy Meadows, where its narrow and the striping was poor. But otherwise, especially around Sherman Pass, there is a very good quality road (but obviously wouldn't be usable in the winter).