I’m not sure if this has a data plate that pinpoints the date as 1943 or if that’s just a guess. I suspect Acme only manufactured the tongue?
https://www.facebook.com/marketplace/item/428123261717216/
“Original 1940s ACME built Willys Jeep trailer. It has been sitting for some time and definitely needs some TLC, nothing a little sheet metal, a grinder and a welder can’t handle. Perfect winter project to get your Willilys ready for car show season”
This trailer is a M100 postwar trailer. Identifying features are the grab handles on each corner of the tub and the curved parking brake handle. I should know as I own one myself.