My spare parts logging caboose bash only used 1/2 a USA boxcar body and roof , after I finished it I decided to try to using the leftover boxcar sides to bash a small boxcar:
the sides and roof are USA, the end panels are corrugated styrene over a styrene base with wood reinforcing in the corners, the doors are from the parts bin and a bunch of USA grab irons.
The whole thing fit very snugly over an basic HLW minicar, painted:
Both this and the caboose are due for an inkwash then matte spray coating, but for the time being they are done.