Thank you Alex! I wish I could help you on this but I'm not really sure how I can do these things.. In fact this structure has had no plans on paper and I have never had to go back and rebuild something because it was wrong. Some how I just know how to do it..I can tell you that when Im working with concrete I just imagine how it needs to be inside of the forms to get what im looking for. I think imagination is the key!You definitely have some talent. You have a really beautiful set up. I regret not standing by my grandfather as a child to learn what it took to build beautiful structures like this.