Many railroads had double door 40 foot boxcars for carrying lumber, automobiles, furniture, and industrial parts that would not fit through the opening for a  standard single door box car.  While a model of this car has been announced by our large scale manufacturers, it is yet to be even put on their new product development pages.  I decided that it would not be too hard to build one for myself using existing parts.  The conversion is very simple, and the end product is a fairly believable model.  This is what I call a "one weekend" project.
    I used an Aristo 40 foot car for the basis of my model.  You can use either USA doors or Aristo doors to accomplish your task.  Both manufacturer's doors are about six inches too wide, but for this conversion the difference is acceptable.  I chose to order two additional doors from Aristo to complete this project.  Unfortunately both manufacturers' doors are set to open from left to right with the latch on the left side, but I felt that to modify a door to open right to left was more trouble than it was worth. I removed the latches on both doors, and also removed the three door stops on the outside of the car.  I did not intend for these doors to open, since I would then have to cut the opening in the side of the car larger. The existing opening is well covered by the doors.  A more determined scratch builder would probably take styrene and scratch build two new doors, and sometime down the road I may also.
    The doors were fitted in place, and extended door tracks were made from "L" shaped styrene stock.  Once the glue had dried, the entire car, including truck side frames, were sprayed with Floquil Boxcar Red.  Once this had dried overnight, the sides were then sprayed with Testor's Glosscote.  My decals were once again provided by Stan Cedarleaf, and in this case they were Cotton Belt, which had quite a few of these cars.  Once the decals were applied and after thorough drying, the sides of the car were sprayed with Floquil Flat Finish.
    I took metal wheels and sprayed them with Floquil's Roof Brown for rust and installed in the existing trucks.  Kadee couplers were installed and appropriately painted with Rust.   Light weathering was applied, and the car was now ready for the main line. I now have a box car with a different look with minimal surgery.