Craig, It is no problemo to drive from Johnsville to La Porte in full size rig or even a subaru. I did use 4wd for some of the ups and downs, but would have been okay in a 2wd rig. However, the road to Four Hill Mine is more jeep-like.
I'll cover the rest of the road in Part Three, which will be another day or so before I can get done.