Jer,
I used thin aluminized fireproof material on the firewall and then a layer of the aluminzed carpet padding. On the rest of the interior I used peel and stick Dynamat and covered this with the aluminized carpet padding. Used 3M spray glue for the whole thing where peel and stick was not used.
In the pic below you can barely see some of the insulation on the passenger sidewall in front of the door.
