Also, Did you insulate up the firewall as well? Cause on My Duster I get a TON of radiant heat off the firewall! that would definitely be a place to do it.
I insulated half way up the firewall, any further and I would have had to remove the heater box and pedal assembly and all the other doodads that are mounted to the firewall. It should knock down some heat and noise anyhow.....better than factory atleast.