I had a look through my "OLD Stuff" boxes, and I came across the programme for the 1973 Grand National at Christmas Hills.  What a catalogue of names and bikes.  A mate and I made the long trip down from Mackay to compete.  Ever seen a massed start with 4 rows of what seemed like 20 to a row?  Or been in the middle of it?  A fantastic track!  If I can relearn how to post photos, I'll scan it.
Mike