Unfortunately 464 isn't a good candidate for repainting as RGS 461 for the same reason that 463 isn't. The wrong cylinder configuration. The RGS has one of each of the groups of rebuilt K-27ss - No. 455, part of the second group of conversions; and 461, part of the first batch. No. 455 which looked like the rest of its group until she ran away and was wrecked on Dallas Divide in 1943, and was rebuilt in 1947 with a cut down standard gauge cab and tender cistern. Two of the second group of conversions survive - Nos. 463 and 464. None of the first group of conversions have been preserved.
The first four K-27 conversions to piston valves were Nos. 454 (3/1924), 456 (6/1924), 461 (1/1925), and 458 (3/1925). These had the valves lined up for re-using the old Stephenson valve gear the Class 125s were built with. All four were apparently rapidly converted to Walschaert valve gear. These were the locomotives with the valves slightly inward from the centerline of the cylinders.
Nos. 464 (9/1925), 452 (12/1925), 455 (12/1925), (453?*) 456 (9/1926), 463 (6/1927), 459 (8/1927), 462 (8/1929). These were rebuilt with piston valves and Walschaert valve gear at the same time. These have the valves slightly outward from the centerline of the cylinders. Note that all conversions to piston valves included superheat EXCEPT 462, which remained a saturated steamer until retired.
Nos. 450, 451, 457, and 460 were never converted to piston valves, and remained slide valve 'soaks' until scrapped; only 460 saw much service after 1929.
* O'Berry doesn't have a conversion date for 453. Presumably sometime between January, 1926 and July, 1929.
CVM
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