Good morning Darryl.
Some knowledgable contributor will no doubt answer your questions which are outside my area of familiarity.
I just wanted to comment on the jerrycans in the photo which I've only noticed on this occasion. They are all of the hybrid variety being of American type 'jam tin' construction but with the German style cam lock spout. These cans seem to have been exclusive to the USMC or maybe the SW Pacific and I've not encountered one in real life. Definitely a better proposition than the screw cap in my opinion and I wonder why they didn't standardise on them.
Apologies for the interjection but it aroused my curiosity.
Happy New Year to all.
David
