This is easier to some extent... but just as difficult to decide. I'm going to assume its tied into the 'What 10 locomotives would you keep' thread and go on the premise that I'd have to do both. That being the case... the obvious answer for me is all 5 (different) Kato California Zephyr sets... which total 55 passenger cars. Then the 5 cars in the Silver Streak Zephyr set too. So... that's a total of 60 cars. The Rio Grande did mostly coal and other commodities hauling. I'd have to keep all of my Rio Grande coal hoppers & gondolas from Bluford, Trainworx & Intermountain which would be about 50 cars. I'd have to cut back one or two to add the Atlas Caboose in the Grande Gold & Silver 3 stripe scheme.
I would have to quit model railroading if I was limited to 110 cars. My Oroville yard would look empty with just 110 cars in it. This is with somewhere around 400 cars in the yard plus another 70 on the main. Rodney
