Ted Doskaris noticed some of the requirements for Kadee couplers on higher stress applications, notably locomotives.

I believe this was coincident on discovering the advantages of center-set couplers and the benefits of better control of the coupler height itself.

He designed and comissioned the manufacture of a coupler box made from aluminum that is similar to the Kadee #911 coupler box (the old 831 type).

He has several vignettes on this.

This first link is the design and creation of these aluminum coupler boxes:



Here's the application on a USA Trains GP38:





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