I would think that in WI you would be in the same situation as I am here in IA in that you have the A/C for dehumidification as much as cooling, so it may not require the SAME size system as the car anyway. I just wanted to mention this in case you hadn't already thought of it. I know for me, I just need a little more something than the vent, cause they don't do much when it's hot and humid.
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