So as i have been doing my interior, I have been adding the insulation as i go along for heat and sound deadening. First i covered the floor and doors in fat mat, then added mass back carpet. I was happy with the outcome but still not quite what i thought i was going to get. I thought maybe i should of done dynomat or spent more money. So i started doing a little more here and there. Did the package tray, finally stopped rattling, did the rear quarters, kick panels, gas tank. Got to the point where i figured that the last thing was probably the headliner and add insulation to that after i go wiht the MTF headliner. But before i do that let me try the firewall piece. I ordered the molded one from CJP and I am really impressed. Not as hot in the car, not as much of a gas smell (cant completely get rid of it until EFI), but the sound is alot less. Ofcourse every piece helps but this was the one piece that i noticed a difference besides the massback. Still have 2 holes to plug in the firwall but i wanted to share my experience.