Since I finally got around to installing my new door handle, I also finally got around to adding some deadening to the door. Took about 1.5 sheets of KnoKnoise Kolossus, split into small pieces, for the door skin. The rest of the 2nd sheet I used on the carrier panel.
A tip - if you are looking for butyl tape in a hurry, Home Depot sells it as sealant for metal roofing. Its cheap, too!
https://www.homedepot.com/p/Fabral-1-4-in-x-40-ft-Butyl-Rubber-Sealant-Tape-40BT/207149821
Not all stores have it, but mine did. I used a few lengths of it rolled into one to fill a lot of the gap between the impact bar and the door skin. The factory filled maybe half of it with spray foam but the rest of it was just a big gap. Doing the tap test before and after filling most of the gap, it definitely made a difference.