If I recall correctly, the Argentine Central was a short lived short line that connected with the end of the Clear Creek line to serve the mines in the area and to run tourist trains.
The steep grades the line had resulted in management in selecting shays as the motive power, thus, a replica of an Argentine shay would be somewhat appropriate to the Loop and an excellent choice for motive power on the Loop.
If I am wrong on any of these details, I would appreciate it if those with more, or correct, information, filling in the gaps or correcting the errors.
Kevin