I pulled the headliner and installed foil bubble pack radiant heat barrier insulation.
Check your local lumber yard (Lowe's, Home Depot, etc.) for the foil bubble insulation. The stuff I used was called Refletix. Pretty inexpensive. Not only does it reduce interior temperatures it also adds some insulation for winter and helps to deaden sound a little.
Refletix runs $.042 per square foot. $42 for a 4 ft x 25 ft roll. Reflects 97% of radiant energy.
I have used it in numerous streetrods, on heat shields, AC boxes, under hood, etc.
The difference is very noticeable.
It made it a tight fit on re-installation, but other than that worked pretty well.
Should help to reduce interior temps next summer, and keep it a little warmer this winter.
