If you guys have access to magazines... here are some sample references

  40' 1939-1946 10'4"IH to 10'6"IH AAR boxcars                       
    Generally: 10 panel, 5/5 ends, W or S corner posts

    RMJ 3/1997 pp.24-29 Ed Hawkins article, photos SSW,UP,SOU,WABASH,SOO,RI,WP,NP
      Cars shown over time in various paint schemes

    RMJ 8/1996 pp.6-13 Ed Hawkins article, annotated roster of original owners (ladders,
       doors, height, corner posts, etc) & discussion of models, with photos CB&Q,ATSF,
       FW&D,IC,CMO,ERIE,SOO

  40' postwar 10'0"IH AAR boxcars

   RMJ 12/1989 pp.44-48,49-51 prototype and models info for NYC,UP,SP,EJ&E,CNJ,B&O,FNdeM
       with accompanying article on C&BT kitbash

  40' AAR postwar design AAR boxcars

   RMJ 10/1999 pp.43-51 Ed Hawkins' comprehensively covers postwar 10'4" to 10'8" boxcars
      with the 4/4 Improved Dreadnaught (rolling pin) ends -- photos DRGW,ATSF,NP,ERIE,MONON,
      CNW,IC,CB&Q,AA,A&WP

    MM 9/1990 pp.24-27 Todd Sullivan article, photo 1938 prototype ACFX #30000, drawings
      or 1948 standard design car, text, photos ACL,ATSF,DT&I,C&EI,ERIE,CMO,ITC,DL&W,NKP,
      RI,SERX,NJI&I,RDG,MKT

  40' ACF cars with "carbuilder" ends

    RMJ 10/1990 pp.52-58 Ed Hawkins' article, roster of cars built w/ rect panel roofs or
      diagonal panel roofs, detail notes for brakes/running boards/door size, many photos
      B&O,ACL,BAR,C&EI,CRR,ITC,KCS,WIF,RI,ATSF,MKT,BCK,TP&W -- plus paint/decals info

Tim O'