I didn't find the serpentine sofa; I made it out of acrylic modeling putty. It looked like Flintstones furniture to begin with - maybe still does. It's fully visible through the observation compartment windows; I'll post photos of that when everything is fixed in place, including the passengers.
All the carpets in the car are inkjet printed on fabric paper. I've done quite a lot of this in the past and have got the hang of it, I think.
There's a drumhead on the rear of the Lone Star car (UP 150th anniversary) that I intend to replace with a 4014 Excursion version. More on that when I actually figure out how to do it.