Another useful doc to add to this...
Unsure where this one came from - found it in an old folder while rummaging for something else!
First drawing - distance piece - is "Plates, Packing, No1"
Second drawing - Wooden Spacer - am not sure... might be the Variometer Adapter Plate... depends how big the US Antenna hole is on the Sherman.
At worst therefore I can make these parts now!
However, it would still be easier to find ready made bits - we have enough parts to make already.
Cheers
Tim