Thanks Gem!
I didn't recognise any of the names on your "other autographs" list, woolongong, so I looked them up in my 1949 "Who's Who in Speedway". Not one of them is mentioned. Maybe they were supporters, track staff, referees, announcers, time keepers, management....They don't seem to have been riders.
Incidentally, England won the Test match at Bradford on 5 July 1947, 65-43.
Scorers:
England: Jack Parker 9, Norman Parker 13, Bill Kitchen 16, Tommy Price 7, Alec Statham 16, Ron Clarke 4, Malcolm Craven (res) 0, Les Wotton (res) 0
Australia: Vic Duggan 16, Max Grosskreutz 10, Lionel Van Praag 3, Bill Longley 6, Frank Dolan 3, Ron Johnson 5, Aub Lawson (res) 0, Ray Duggan (res) 0.
There's quite a few different names there to the ones you have.