Long time ago in a different lifetime I ran Superformance #1855 and #2584 with a 427w and carb. Did have some heat issues but probably wasn't as hot, easily as humid. Probably wasn't as bad as OP's experience.
ProSystems 750 DP, mechanical fuel pump, factory fuel lines. Premium 93 or 91 as available.
Added the phenolic spacer, about .5" thick.
Plumbed in an Aeromotive bypass regulator after the carb. Ran 5/16" return lines.
Wired the radiator fans with a manual override switch. I think I ran a 160 degree thermostat.
Also ran a Setrab 915
oil cooler with the Canton thermostat and AN-12 lines.
Usually if I could keep moving there were no problems. No issues with idle unless for an extended period. Never noticed a significant power reduction.
But, when idling in traffic, think Woodward Dream Cruise, lifting the hood on the latches helped along with turning on the fans before it got hot. This opened a gap of about 3/8" along the back of the hood, usually solving the problems allowing the heat to escape. Never had a problem with the rear of the hood up, other than the hood would shake a bit more. Many owners did same w/o issues.
Now I did have that one time I drove I-80 from Lincoln, NE on 104 degree August afternoon. If I would have had a turkey baster and sufficient supply of water, I would have been "done" and "juicy" when I got to Colorado. As it was, I was bright red and crispy. The car was perfectly content running at 95.
Jim