I am very impressed with sincerity of your effort and workmanship. Much to learn here.
However, I have to question economic viability of this project, due to your need to pay for air conditioning.
Air conditioning in Dallas will probably triple or quadruple your power bill, compared to a naturally cooled installation, and cost of power may make bitcoin mining unprofitable much sooner than for those without the need to pay for A/C.
True the ac doesnt help. It uses about 1500w, or 3.5 oc'ed antminers worth of power. Based on my power rate, thats about 3.64 USD per day. Not horrible. Not great either. Also, if we leave the door to the shed open when home we can shut off the AC.
If you do not need AC when the door is open, then what you need to do is get rid of the AC, and instead install an exhaust fan. You will pay a fraction of the cost of electric bill.