Same model here. In Galveston it was a little hard to manage the cooling but I started to do some small tweaks. Insulating the the cold air and the hot air return. Making sure there was no air escaping in between.
Pray for a shades area and use the awning.
Get it nice and cold early in the day. I do this at home too. Most of my rear vents are shut and the rear AC is used to support the front. I run them on high when needed and don't let it just use auto.
Shades pulled shut at least on the sunny side. Might modify the covers to the AC inside and add a vent. Need a little bit more time to see if that's really necessary.
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