Interesting. When we were staying in Newhall a couple of months ago, we could see the site of the Deadwood Set just down the hill from where we were staying. I didn't have a chance to visit (nor a reason to) but that probably explains why SP M-4 Mogul 1629 now is at the Saugus depot in Newhall (it was with the 463 at Melody Ranch). Additionally, there are only two SP M-4 Moguls in existance, there and right here in Tucson!
I always wondered where Melody Ranch was, and now I know!
Bill Daniels
Santa Rosa, California