I'm honestly not sure if the "I'm not buying it" is a joke or not... but in case it's real...

1) If someone did cut up a real GP35 to build a movie prop, the locomotive wouldn't be valuable enough to then put back together.

2) Both the real one and the fake one are still out there, one in Fillmore and one in Los Angeles.

And if you were just pulling my leg to see if I would respond... yeah, you got me. But if not, the way you can tell straight up, is if you look at the link you sent me of it being built, you can tell with just a few moments of looking at it that engine, it's not as large as a real GP35.

Also, if you look at the link to the image I took of the fake one on the street, again, once you look at it for a few moments, you will realize, it's actually about 4/5s size.