Check the weather before you go, it can be COLD up there. They have closed highway 108, 24 miles from Strawberry, which I am pretty sure means Kennedy Meadows. That means all your plans are still good to go, and you should have less traffic since people got scared off.
I am not Darryl, but I am pretty sure he means the super steep part that goes east from Kennedy Meadows as the "Sonora Grade". It really is spectacular, and there are forest service roads that allow dispersed camping with a permit. Stop at the Ranger's Station before you go, but you have to get there before 5:00. There is one at Mi-Wuk that is right off the road. The Sonora station is off Greenley Road, but about a mile from the highway, opposite Sonora Elemetary School. I think given the weather this week, you shouldn't have any trouble finding a spot, but fishermen always surprise me.
Thanks guys. Since we can't leave till 5 pm from the Bay Area on Friday, I reserved a campsite at Pinecrest Camp for Friday night. We are planning to wake up a little early on Sat and drive up to Kennedy Meadows/Dardanelle area. My wife is pregnant we are going to take it pretty easy. Thanks again for all the advice.
BTW - Here is a good campsite map of the area:
http://www.sonorapassvacations.com/lodging/campgrounds.html#map