In 1967 the Texas & Pacific Railroad took delivery from FMC Corporation of 1000 100-ton covered hoppers with road numbers 715000-715999. The cars had a capacity of 4526 cubic feet and were similar in design and had the look of the Pullman-Standard low-side 4427 cuft covered hopper. Comparing the Missouri Pacific mechanical department freight car diagrams for the FMC 4526 and the Pullman-Standard 4427 diagrams found in the Car and Loco Cyclopedia the vast majority of measurements between the two are within one inch with a few notable exceptions. One key measurement difference is the inside length of the 4427 is about 7” longer than the 4526. The running boards are also about 7” longer on the 4427. Without a better set of diagram I am unable to find the difference where the extra 99 square feet in capacity is located for the FMC 4526. For my modeling time frame of October 1979, the FMC 4526 made of over 13% of the 7000 plus covered hoppers o...