Below is a US Army WWI infantry kit, several companies including Tamiya make kits of WWII Us gear. Swap the German gear with the US gear and maybe keep a few German items like the German gas-mask container, your call.Any consensus yet on what the basic American infantryman looks like? I plan on ordering some German infantry models to make some Yankee Joes, and I’m wondering what bits of kit can be used to differentiate them from the OTL Wehrmacht.
You could mix n match some German gear too.
You could also toss in some Italian or other nation's kit for variety, use your imagination.
You could also try cutting sections of weapons (rifles, sub-guns) to make new guns.
Good luck and looking forward to seeing what you come up with.