It wasn't to bad, I pulled the headliner and it was sagging so I took off the original carpet and under was rotted 90s foam, however i wanted to save the cardboard that was the correct shape and stuff, so I took a firm brush and scrubbed the whole thing and it came off prefect, it was a little trick I found on line, After that the firm cardboard let has some rips in it so i took tap and covered the side that will be on the ceiling, this really helps firm up the shape a lot. I ordered a new carpet for the top from the company Texas Foam and Fabric and it is about an 8th inch thick foam with a darker grey carpet than the original, should look really good and its very high quality. Ill Post some pictures of it when i Finnish it, trying to keep on top of my mechanical engineering degree can be hard tho.
Are the speaker boxes that you have custom to the car and go somewhere or did you just have them in the trunk?