Looking for Kern River Hot Spring via Mineral King station info

I haven’t done that hike since 1982.  Did 1.5 days in and 1.5 days out with a day exploring the river and soaking in the hot spring.  Very enjoyable and worth the effort.  Saw one person the whole trip that was fishing along the Kern.  I am sure it’s more crowded now.

I am making an AllTrails custom map as there is no official trail to Kern Spring I can discern.

This route gets there, but is 30 miles/7.5k vertical and other articles refer to a path that is about 20 miles/6k vertical. Is there a path in the valley (indicated by the dashed red line) to follow? Or is the stream bed walkable? Or can anyone point me to the best path to Kern Spring? Here are my options as I see them now –

North Route – 31 miles, 7500 vertical. Not Ideal because the end of day 1 would likely leave me above the tree line and I hammock

South route 32 miles 6000 vertical. This could work, as 15 miles gets me off the ridge, but 32 miles is still farther than ideal.

Here is my ideal route, but the section in blue does not show a trail there. its 17.5 miles with 4600 vertical. If anyone knows this area, do you know if the stream bed is walkable? It looks like about 3.5 miles in that valley, but that cuts off 13+ miles compared to the North or South loops. I think I could do this in one day

Here is a closer detail of the area in question

Last, how hot is Kern hot spring? Sespe is burning hot at the source and you have to go down stream a ways to find a nice pool. Is Kern at least hot tub temp (>104*)?

Thanks!