I love my newish 2019 S with Rex. I have done a few trips from San Jose to Pismo in one shot but as you know running the AC greatly reduces range. I just had the windows tinted and plan to add an extra fuel tank with a transfer pump eventually but with the price of gas lately getting the most out of the batteries is ideal. I am currently finishing up an aux air conditioner made with a transmission cooler with four 120 mm fans with ice water pumping through it. I'll utilize a couple motorcycle batteries to power the pump and fans. I made a frame and will mount it between the seats blowing forward. It will also make a nice barrier to keep my dog from inching forward. The spinning blades will keep his whiskers short!
I will post results when I finish.