I believe you just won your case sir!
Please google.com this address:
19350 Goldenwest St, Huntington Beach, CA
Then do a satellite view, and zoom allllll the way in. You will find that he had a stop sign!
Zing! Failure to yield written ALL over this one Glen.
Print the google.com map out (you'll need to print screen probably to get the satellite view). If you can't do it, I've just printed it out and I will fax it over. But the quality might be pore. It's best if you can print it (I can mail it as well if you need, but I need an address).
MAKE SURE you give a copy of your diagram and google.com map to state farm. This will help for sure!
Now for the damages to your car...
Once Farmers decides they are at fault, I have no clue if the damages will total out the vehicle. You can definately take the check and fix the damages on your own, but again, I don't know if it give the car a salvage title.