It depends, I would leave the vests off unless it was close in time to the Normandy landings. I've not seen a lot of pics of people wearing the vests later on into Normandy, Just around the time of the landings.
Avoid 21st's neon green gear at all costs! The stuff you want is the khaki brown. By the way, it is not khaki and should not be portrayed as khaki. There gear is olive drab No.3 (OD.3) or OD.7.
OD.3 is a lightish olive drab and OD.7 is more of a green color. By the time 1944 came, OD.7 and OD.3 gear are being mixed.
I mix brown and green to make a dark olive, then add white to taste to make OD.3. If you want OD.7, just leave it on the darker side.
See how he looks. THe gear and M1941 Field Jacket are Olive Drab No.3. Notice that it does not look like it is khaki.
Here are some examples of the colors I found on the web.
OD.3
OD.3 Also note, it real life, colors vary a lot. Different manufacturer, sun effects, weathering, ect...
Here are some repros.
This is a GREAT example.
So, you just have to do your homework.
Also, I do not think M1941 Field Jackets ever came in OD.7.
YOu should also look at Dragons US figures. Their paras are great! They also have a set of 4 figures in green. I forgot what they are called but they make great US figures in Normandy. They are wearing the 4 pocket M1943 Field uniform. I think that is what they are called.
Yea, they would wear the "Backpacks." They would wear the M1928 Haversack (Has not been made in 1/18) Or the M1936 Musette Bag.
I hope that helps inform you a little!

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