Need a little help for some British friends on route planning

This might seem to be a bit of an odd request but I thought perhaps some of the SOCAL adventure guys could help. Some Brit friends are riding across country and will be stopping in Lone Pine on 395 with their next stop being Three Rivers out of Visalia. They have asked if there is a route through the Sierras so they can avoid an long detour south. I am unfamiliar with the area and don't have a topo map. However my Rand McNally state map shows a paved road west out of Independence which joins a limited access road that eventually comes out on 180 north of Lone Pine. Has anyone made this cut? Does it really exist and is the road paved, gravel or other? Another route appears to be the J41 west off of 395 just north of Pearsonville. I believe they'll be riding rental bikes which probably means Harley.

I ask the question because I have ridden my GS on some of these roads marked as "limited access" in Idaho and eastern Oregon and they were rough paved. The last time I was on one of these, we had joined up with two guys, one on a Harley and one on and old Gold Wing, and they did fine.