I looked at a few period images of carts and worked up a quick model that would scale with the 40s. The entire wagon took only 30 minutes to construct. Basically the matchsticks made a frame and the strip material made the bottom and sides. The plastic wheels are already drilled for an axle and I just trimmed a matchstick to fit but next wagon I think I will get some brass wire the correct size to make the axle a bit sturdier.
The model was entirely glued together with my favorite whiteglue (Weldbond), and a quick stain with a mix of brown and black "Didi's Magic Ink". I "wetbrushed" a little bit lighter brown overall to get the black plastic wheels colored. I then added some tissue soaked in white glue to make a load, glued it to a cavalry base and I'm letting the whole thing dry overnight.
Tomorrow I'll paint the load and drybrush everything to weather it and it should work out ok. No horse teams yet but I'm on the lookout for a set of kids farm horses that might scale about right. For now these wagons will work to mark out a baggage train perimeter or work as bridge barricades (like the one defended by the dragoons at Cropredy Bridge).