Johnsti:
Do you know how to get to the gate? There's only one gate, by the way, and it's cleverly hidden in the arboreal forest. I know how to get there -- but do not know the names of the roads so can't give you any help there.
The gate is usually open Thursday, indeed, as MiltonP has stated. I don't know if any/very many folks are going to camp there that night, so you might be wise to consider locking your trailer and hitch for the overnight. Friday and Saturday there'll be plenty of folks around -- security will be pretty good.
See you in a few days.