Our first big tour was Canyonlands II out of Knab Utah. At that time our pickup had no top. I recall one day in particular when it was 104 F and the wind was strong out of the Southwest. It wasn’t the sun or wind that bothered Marge the most, it was the hot floorboards. She spent most of the tour with her legs hanging over the passenger door.
When we returned home I added a 3/4″ thick pad of insulation under the floor mat, the kind I used under the hood of our 1962 Tempest. It helped but on hot days her feet still sought respite from the heat. This spring I installed a new tailpipe and wrapped it with heat tape from a hot rod shop. It made quite a difference, but on our recent tour to Cypress Hills, when the heat wave approached 100 F, her legs were once again draped over the door.
Aside from passenger comfort another good reason for the tape is to prevent the floorboards from catching fire. I know of two instances in our club where members were glad they were carrying extra water for the radiator.
Here’s an afterthought. Perhaps like me you have found the exhaust pack nut is prone to back off. Model T parts vendors have a ready made solution. This is what I did.