The numbers match. Thanks for the copy of the SV record sheet.
Back in '76 Mall Ferrell wrote to me:
"The WP&Y received their former SV cars in several batches. First, in 1942 the United States Army, which was operating the WP&Y, obtained the following Sumpter Valley cars: Date of sale was 8/30/1942:
"SV Flats 76600, 76614, 76617, 76628, 76633, 76640, 76646, 76661, 76668, 76680."
I have a copy of WP&YR equipment diagrams and one of the sheets are for Flat cars 317-326 (except 319) and it states "Purchased From Sumpter Valley Railway."
I think one of the White Pass drop center flatcars had ex SV Vulcan trucks.
Brian