I have been considering the same basic set up. I also live in TN. I am not worried so much about the winter, as that can be solved by a small space heater of some sorts, but the regular 95+ temps, for what can be weeks at a time, in summer have me worried. I have never really paid attention to what the temps in my garage are during the summer though, just never had any real reason to think about that in the past.

If anyone has any suggestions or experiences, they would be greatly appreciated.

John