Joe, electric is not my profession nor do I claim to know it all. That being said I just wanted to pass along something told to me from our local electric supply co. They have been in business more than 40 yrs and that's all they sell is electric supply. I had a small project running underground electric to an out building (10-3 with a ground rated for underground). I mentioned to the guy about running it in conduit; he said absolutely not, as that it being rated for underground is made a specific way that allows heat to dissipate. Running it in conduit could allow it to over heat and melt.
My 2 cents and may the wiser heads comment
BTW, the shop is looking great.