Hi there,
I am also interested in Swiss Z after visiting the Gotthard three times before the new tunnel opened and becoming foolishly convinced - while staring at the town - that I could build a model of Wassen on the size of a door.
My trials and tribulations of building a Swiss modern image layout out of foamboard and kitbashing/painting/building in a scale and prototype I've not tried before are loosely detailed here : https://zwassen.blogspot.com (https://zwassen.blogspot.com)
Including, among other things, repainting my passenger train into the current scheme
And repainting a pair of locos as BLS:
Cheers,
Darryl