This may be of very little help to you, but between Ennis and Dallas, right on I-45 I saw a fairly large beltie herd just last month. Heading from Ennis to Dallas it was on the right side of the freeway -- can't remember if it was closer to Dallas than Ennis. I was real surprised to see that herd and they really caught my eye. Sorry, but I didn't see a sign with a ranch name.