For a party of nine, I'd look into a shuttle of some kind. I'm not a fan of driving LA traffic either.
My grand-daughter wanted to add a day on our October trip to check out USH's WWOHP. When I found out the travel distance and time, I was looking for ways to avoid going to USH. My solution for her was a one-day trip in June.
I found it was less expensive (thanks to air miles) to do a one day trip from PDX to BUR. We had one LONG day, June 7th when we went to USH.
It was well worth it for us to do it this way. The stress of leaving DLR on the Oct trip isn't an issue now. aaaaaaah......
Geemo