Cool video. 4501 is a legendary engine. I got to see her just once at the Tennessee Valley Railroad Museum, but she wasn't running at the time, back in the 1990's, and was painted green.
I rode the October excursions from 1976 to 1991 behind 4501, 611, and 1218. I saw the 765, 2101 in Freedom Train colors, a "Southern" 2716, CP 2839, T&P 610, and Savannah and Atlanta 750.....01 has always been my favorite steamer, even in freight black which I prefer.