I've classed Americans at San Antonio and Houston before; I even served on state committees that set guidelines for classification of steers in Texas. I can tell you that a long sheath alone, will not necessarily get you in the ABCs. It's more about breed character, specifically in the front 1/3 of the body. Your calf must exhibit the correct ear length and outward/downward angle to it. It must also possess a bos indicus type of head and eye shape with some extra throat and dewlap hide. Sheath length, for anyone that knows what theyre doing, is not a big priority.