The one modification that will help the A/C cool the truck easier is Ceramic Window Tint. Have it on all my glass (windshield as well, 95%) and it helps immensely. The truck probably cools down in about 60% the time it would take without the tint (especially in full sun).
This... Can't tell you how much I miss ceramic tint. Unfortunately I didn't order my Raptor and it already had $tealer tint (shit) on it. Now I have to find a good shop to not only apply, but remove.
I also live in Central Texas and my last vehicle was black. Not a problem with 2007 era ceramic tint on a daily driver.