Posted this many times, but here's one of my Big Boys on 70" radius (0-140, in 3R langauge). Even here, the overhang is more than expected, 108 or less won't be much improvement over 0-72 in my opinion. I can't imagine running one of these on anything less than 65" radius (0-130) but that's just me...
It looks much better than a 4-12-2 rigid frame on the same curve, however. It's another one that looks ridiculous on 0-72.
Whatever you decide, enjoy your Big Boy, it's a great locomotive.
why do you still have the packing material in the loco?