I don't know if the HOA supports it, but I'd look into an extended height carport. That way, you can not just get the sun off the Excel directly, but have the ability to open a roof vent and run a fan (I'd probably use a box fan) to keep the air circulating inside.
If a carport is a no-go, I'd look at a Maxx-Aire cover for the ventilation cover, a Fantastic Fan upgrade (preferably to a model with a thermostat), and use that to keep air moving. Yes, both of these cost electricity, but this is definitely a lot cheaper than constantly running the A/C.