Re: 493 in a different Universe-OT already

I'm getting of track real early for which I apologise (I don't really!), first up, love these photos of dual gauge trains, this aspect of DRG&W operations fascinate me.
But the operations also intrigue me, can any one answer my questions?
1) Are all SG cars destined for Antonito and places beyond or were some shunted out at intermediate stations?
2) Having seen photos with SG diesels up front, would that train continue south, leaving the narrow gauge section of the consist at Antonito, would the dual gauge idler flats continue with the train or stay at Antonito?
3) Was there any particular train that ran as a DG train or if there was loading to go it just went on the first train, be it NG or SG?
4) If it was a NG freight, why take SG loading, surely that is double handling for it to be shunted of at Antonito and be picked up by a following SG train. Or would that SG loading on the pictured train only be going to Antonito anyway?
As I am asking these questions the pattern of operations are formulating in my head but some confirmation would be nice, I see some intriguing model railway opportunities here!
For clarification, NG = Narrow Gauge, SG = Standard Gauge, DG = Dual Gauge

Intrigued Wayne from Oz