new guy here, in wyoming. Have '55 first series, 3100, 5 window, with factory hydra matic, 235. My q. is.........I understand that the engine color is stock grey. I also know that a different engine was used with a hydra matic. My engine #'s tell me the engine is indeed the correct one for my all stock truck with the hydra magic. I don't believe the engine has ever been changed or altered. My engine is orange. Also was it a bigger H.P. engine that was used with a factory hydra matic????? I have tons of other q., and am looking forward to using this forum, if I can figure out how to navigate it. HEY, out here in Wyoming trying to get my sweet little truck on the road again. Larry