Thanks for the post Steve. I like the idea of adding a 1" pleated filter in front of the indoor unit and will be looking into making or possibly buying one, if available. I hope the WEN air filtration unit that I'm installing helps with the dust. To help with the temperature I'm installing a radiant barrier under the R-13 faced pink stuff. Should help with the sun issue here in So. Fla.I'll be talking to HVAC guy about that filter when he comes to install the unit.
Funny how things go. Just when you think you've created the the best plan to get your shop up and running, you run into stuff that prolongs the process. I'll get progress pictures as I get really moving.
The electrical should be done by the weekend by a licensed/certified electrician. I have a 60A breaker in the main panel in the house and had a 6/3 wire run through the attic to a junction box outside the house and in front of the shed. He's running 6g THWN wire underground in a schedule 40 conduit into the old 150A house panel I'm using in the shed, then 12/2 & 14/2 Romex to the outlets. The 110v/ & 220v circuits are going to be on 20A breakers with each of the 6 220v outlets on individual circuit breakers. The 110v outlets will be split into 5 circuits - main lights, supplemental lights, air filter, AC (the mini unit is 115v), and 6 outlets.