I caught sight of this loco years ago in "Steam Locomotive Cyclopedia-Vo1 Model Railroad." What a Beast, there was an image of the loco negotiating a switch with crew members watch each drive wheel making sure it did not crawl up on to the rail.
The Beast! The UP 9000 series .
Now if you look closely at the pilot deck you will see the operating Greeley Valve Gear on this MTH model. It also has the third cylinder with piston rod connected to (if I recall right)the second drive axil. The one draw back more moving parts to lube!
Ron