A rather simple kit bash from a P2K 52" Greenville gondola. Made in 1953 and came new with roller bearing trucks. Like others mentioned, since this was in direct service on the WP (straying off the WP only to get to Pittsburg CA's steel mill on the Sacramento Northern-a subsidary of the WP).
Western Pacific had 29' gondolas made specifically to haul coil steel. The coils were loaded over the trucks only. They were loaded on their sides in cradles.
Santa Fe Springs CA