Central CA I-5 to Borrego Springs

I think I'll try the route djgarcia suggested. I've been on CA-58 and US-395 before then down through San Bernardino and Redlands. I'm interested in trying the bypass route north of San Bernardino. As several have suggested it looks like 86 entering Borrego Springs from the east is preferred. Before I wasn't looking at the terrain west of Borrego Springs as closely as I should have.

Thanks,
Neil