Thanks for the great information David, I have 3 different cams Jack gave me one he said was for Mount Druitt (I think it was what Johnny Shanks was running ) One was an Art Senior cam that he gave me a fancy fuel recipe for to use with that piston I showed with the hole in it (I was running straight methanol as half the ingredients in Arts magic mix were not available so that may have been the reason the inlet leaned off and froze solid with ice) Jack wasn't that close to Claude so the other may have been one of his own grinds as it also has a series of two holes either side of the keyway which I am not sure may have been an attempt to mimic the adjustable timing they had on the Manx's or just for balance.
When I reassemble the engine I will clock all the cams to find out their timings.
The timing cover with the external pump I called a rotary is indeed a gear pump I just called it rotary to differentiate it from a piston pump.
The head does have an offset spark plug I have attached a photo.
When you say through bolted do you mean the cylinder base studs are replaced with bolts?
Again thanks for the info, I hope my engine isn't the one that was in Johnny's bike that was involved in a fatal, I should try and trace the serial number as there weren't that many that came to Australia.