Yellow was only on trucks per one site. I'd go Int Harvester red. But without a stock color (50 years old to boot!) next to it it would be hard to tell if it were wrong. My harvester red block compared to the stock oil pump shields that were covered in grease from day 1 probably showed a more orange hue on the originals, enough to make me paint the originals the new red. Had a stock cast iron pump that was a darker red too so its hard to tell what was correct.