In my case, I used double-sided tape for this replacement. The most important thing in this step is not to make a gap when you cut and put it on the speaker. Even just a little gap will make sound distorted.

Also, I noticed the structural differences between 2016 and 2017models. The right one is 2017 model and the left one is 2016 model from iFixit. Sound absorbing material is slightly different as you can see at the third picture, but I couldn't tell the difference of sound quality.