Hi Rob,
A few years back, Mike Cecil who at one time worked at the Australian War Memorial, wrote an article for a magazine that I am editor of, on mobile laundries used by the Australian forces.
See link below,
https://docs.wixstatic.com/ugd/494429_d2e08b1015ea42e6810ca4b0ac9693bd.pdf
The article is the copyright of Mike Cecil.
There was a follow up article from Mike on light laundry trailers which is not on the web, but if you send me a Private Message on this forum, with your email address I can send it to you.
regards, Richard