Thanks for all the comments and suggestions but I am out with the Mustang. If the interior heat thing was my last obstacle I would continue on but it was just the latest in a series of unexpected set backs I still needed to deal with. The interior heat problem is going to take quite a bit of time to resolve. If the inside got to 113 deg in 10 miles I am not sure what it would be like after 250+ miles.
Drag Week is out, but don't lose momentum!
The two things that made my car comfortable in almost any weather, without the AC on, was coating the headers and the hood scoop. I forgot what you have for a hood on yours but the big Boss 9 scoop on mine helped a lot. I have always wanted to ceramic coat the intermediate/H-pipe but never needed to.
A couple other things, you could put a small air dam under the bumper, could make a low pressure under the car which will suck air out, , and last make sure you have enough initial timing. Late timing can raise the EGT and let the headers glow
Insulate the floor, insulate the cowl, helps you feel good but will eventually heat soak.
One last thing is fresh engines make a lot of heat, especially with standard tension rings, it could cool a little on its own, but likely not to the extent you want it.
Sorry to hear you are out, but still eager to hear about some big comfortable road trip when resolved!
