Drew -
The first mountain was mined for gold from the 1860s to the very early 1900s. There were no rock trucks, Henry Ford hadn't even built the Model A yet. By the 1940s the area was essentially abandoned except for some small claims that are still maintained today on a mom-n-pop recreational weekend scale. The ore was partially processed on-site and the concentrate was hauled out by pack train. The roads post-date the industrial scale mining activity.
The other mountain ... that's a good question, I don't know how the material from the top was removed. The present road was never suitable for a normal dump truck, never mind a big earth mover. There's a logging trunk, a very major one, somewhat down on the west flank. They may have used a conveyor, that was done here some. The current road to the top is a collection of hairpin switchbacks too short for a double cab pickup to go up without backing an jockeying around them. It was built to access a fire watch tower that sat on one corner of the leveled off mountain top. That was removed in the 1970s and the road hasn't been maintained since.
Dangerous? Yes. So? There was no OSHA, little if any regulation, lives were cheap and many were lost ... that's the history of building the west. No different mining, road building, logging, farming.
I'm not divulging the specific locations.
MIB