[venum14]

Jon:

The fiberglass will provide some insulation but I would be most concerned with the areas of the footboxes near the headers. Without insulation, you will have a built in heater for your feet and legs. Since I live in the California Central Valley we have plenty of summer heat so I didn't want my shoes melting. This is what I did but I have aluminum foot boxes and interior panels:

1. Double walled the front and engine side of the foot boxes (Kevlar/foil backed insulation sandwiched between the two layers of aluminum)
2. Installed Dynamat Extreme to all the interior panels including the firewall

My car can be driven comfortably in the summer and I even crusie in summer parades with shorts. In my opinion, a little time and money spent on insulation will avoid ripping out the interior and doing it again!