This is an awesome short video shot in 1958 at Spa.
Some of the track looks similar to sections of Mulholland.
This was sent to me by Larry O'Rourke. He used to live above the Sweeper in the late 70's and early 80's and would participate in Grandstands regularly.
http://www.youtube.com/watch?v=2awF_llf7q4&NR=1