I used rattletrap on floor and firewall but used this stuff in the doors
https://www.lowes.com/pd/Peel-Seal-I...ashing/1018733
Bought it at lowes and it comes 6" wide already, I just cut it for lenght and fit it through the panel in the door leaving the paper backing on most of it and peeled the paper off with one hand and pressed it on with the other.Works great and most of the reviews for this product is for guys doing cars sound deading