With regards to the original "Spirit of 76" train. This was the press release name IIRC. It was put togeher as a sales tool for a new Imodal symbol operated by the three roads. The consist was the SCL GE-U-something, the Santa Fe display car, MAYBE another Santa Fe Heavyweight, then a Frisco 40 ft box(this was the junk car for the storage of all the steps and other support material and was usually a track or two out of sight and as stated the Frisco caboose, wide vision, IIRC.
On to the worm, Ths was actually built as a operating model and run on a test track for a time, most likely under heavy security in the R&D Dept. at Topeka. Again, IIRC, the power was to be the usual prime mover to Generator/Alternator then to traction motors on each or at least many of the axles. The containers that were considered were built in full size. When this train did not develop they were offered as bulk loading containers. As an aside, Anyone remember the "Conditionaire" covered hoppers? The containers were a inverted "u" type construction and were designed for the bottoms to only be a few inches ATR. They did not go over well and for years several of them sat at San Bernardino and more were at Hobart yard in LA. One or two made their way to the LA harbor at one time also; all used for company storage.
What did come out of all these fits and starts was the 10 pack "Fuel Foiler". We all know what kind of revolution in Intermodal handling that started. Andy