Lots of places to camp up there so no worries. I am guessing that it will take you at least an hour, maybe more, to get from Kernville to the Blackrock Ranger Station, and about 5-10 minutes to get to the trail head from there. It has been a long time since I've been on that side of the mountain, sorry I don't have a better time estimate.
My Jeep is stock with 31's and I do just fine, there is nothing on the road to the meadows that is that hard and I only had to use 4WD once or twice that day. There are a LOT of side roads up there to explore so plan on an entire day to see it all, they all are dead ends as the meadows are surronded by wilderness and the main road is the only way in or out.
Hey, I'm new to Jeepin myself so no worries, it's all about having fun isn't it!
Hope to see you up there, you'll have a good time.