I have an Atlas Classic GP7 DC loco (48031 Santa Fe #2696). I found a good deal on a Atlas Master GP9 with DCC (40002967 Undecorated, with NCE decoder). From what I have read, the GP7 Classic shell should fit on the GP9 Master chassis, correct? Well, we shall soon find out!!! The deal was too good to pass up... Yeah, I know what that means.