Brian,
When powder coating, you are expelling a cloud a paint dust around the part and the charge pulls it onto the part. That fan may disrupt that operation. The gun air pressure is less than 10 psi. (I use about 5psi.) I hate to be negative about such a nice job, but I’m guessing that will be way overkill.
The other thing is, you need to be able to get around the part, and under it to get good coverage. Shooting just from the front will leave one side thicker than the other.
I use my wife’s old cooling racks so I can spin them around and they will fit in the toaster oven or my big oven without disturbing the part. Every so often, I have to scrape off the paint so it keeps good contact to the part, anything charged will attract the paint!
I powder coat whenever I can, especially if I want a very durable finish. It is so nice when you can install a part just after it cools.