Hi Strthoky,
I'm pretty sure that a double exposure must be used to get the effect you want.
You need a non-blurred image of the loco merged with or superimposed on the blurred image, so you can see the loco details in focus.
You may be able to use your Photoshop to cut + paste, but you won't get the blurred effect on the loco itself. I would say that, using film, you should use a black card to block out the background (only behind the loco/train itself) while shooting the blurred image. Then shoot the fixed image on top with the loco at the same location it was when you closed the shutter on the previous image. That way you don't see the background "through" the train.
This takes a lot of trial and error, maybe there's some other software trickery that will get you what you want digitally.
