Yeah...I see somewhat of a rat snake pattern in that last photo.Looks like maybe its a rat snake.
What, this little cutie?
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Corn snakes come in lots of colors.Was going to say a corn snake, the rat snake's cousin, but I'm going with @rockm. I have a pet corn and he looks quite similar to the pictures, only a different coloration.
This step is 5' wide. If you stretched the snake out it would be very close to 5 foot.Looks more to me like a gray rat snake. I don't know the trans pecos but when I look it up the pattern is wrong. Either way it definitely looks like a rat of some type though. The second and last photos give a rough idea on size. Those bricks look fairly long in the second and it looks like it's by a 4x4 post in the last.