Best route to cross California's San Joaquin Valley and up to Oakhurst?

[Bclayden]

Specifically Patterson to Merced.  Then Merced to Oakhurst.

I know this is an obsure route (actually it is part of a much longer journey) but there are a myriad of road options and none look very good to using Google Map. Options in the valley all appear to have either No riding shoulder, heavy traffic, unpaved roads and the rest. Options in the Sierra foothills are numerous and round-about. Surely there is an optimal route?  Roads to avoid are just as useful.

I can live with having no riding shoulder or some truck traffic...just not at the same time.

This forum has helped me with this type of thing in the past so hoping someone has a suggestion.