I am sorry can't really help since we factory ordered our slide toppers. They do help in keeping the camper a little cooler but not much. We where in Traverse City MI two weeks ago with 90+ Temps, but low humidity around 50% in full sun light and no shade. We did run both A/C's during the day and the camper seem to stay around 74 to 76 F. Which is comfortable to most people, at night the front A/C is shut off and we run the rear fan on the A/C in the low power setting to move the air around.
One thing we are now ordering is a sun shade from Shad Pro, this attaches to the awning shade and helps to screen the entire curb side from the sun. This too will help in keeping the camper somewhat cooler with full sun light on that side.
2016 34RL CC; 2008 Ram Mega Cab 2500HD, 6.7L, 68RFE 6 speed, 4X4, Smarty S67