Les you have a piece of history.... Mark Yeamans built the hoot whistle out of a length of superheater flue. It went on a standard 5" D&RGW base. He installed it when no one was looking (exact story of how he killed the engine, and fired it again with no one knowing is a mystery). Rich Braden was the runner that day. Legend goes he sat on the seat gave the cord a yank and the 484 said "Mooooooo". Rich got this sick look on his face and "uh, no, this won't do".
The whistle made one trip to Antonito and got removed. The hunk of superheater tube was still hiding in the Chama storeroom last summer.
Mark, being an excellent guitar player, built a few more whistles over the years that sounded much better - if not exactly appropriate for the NG. He built a beautiful BIG 3 chime pipe number that sounded like 844. It was on 487 for a few weeks. It was cool but sounded out of place. I recall making out an engineer's report for engine "844487" with such defects as "ATS doesn't work", "engine vibrates at speeds above 65 mph", etc..
Also (you need a big monitor for this) 484 is wearing the remains of a movie paint job. There is a gold stripe around the lettering on the tank. I was there with friends in July, 1980 and 484 still had "201" on the spot plate and on the back of the tank. The cab had no number, just some mismatched green paint.
We chartered the 05635 to Osier and back... just like in the picture. We had 484's normal whistle.