Reply to "Source for older model 4-6-2 pacific steam engine"

What Palallin said.  With those turn-of-the-century high domes, I would start with a 4-6-0 or even a 2-8-0.  Detail and decal it for the GN, to look like the loco in the picture.  As to the wheel arrangement, a chassis transplant will take more than just a Dremel tool and some bondo.  So I would squint hard and use your imagination!