https://www.ffcars.com/threads/cockpit-heat.284055/
Larry H. Miller (previous owner of the Utah Jazz and Larry H. Miller car dealerships in the western states and believed to have the largest private collection of C*br*s, 15 of them, in the world before his death) lost three toes because of the heat. His experience was not in an FFR, but instead in CSX3032. And his problem was at least partly due to the symptoms of sugar diabetes.
Larry took John Stockton out to his new track to drive CSX3032. Larry drove first and then let John drive. John drove for quite some time and when they were done Larry's feet were burned so bad they were bloody. He didn't feel it because of the diabetes.
Anyway, the potential for heat is real. Follow the advice of insulating the foot boxes.