About five hours total, taking my time.
Fabric (one yard at most)
Trim material (if needed) (100 inches in my case)
Hot glue gun
Boxcutter for when scissors won't work
Toothbrush for cleaning the hard to get spots
Marker for making pattern
Newspaper for cover up during spray adhesive
Gloves will keep your hands free of adhesive
Step 1: Strip out original liner (&trim)
You may want to shake or vacuum out the suitcase before you start this step. There will be plenty of dust flying around and vacuuming may cut down some of that.
I pulled up the edges of the trim and found an area where the liner was already coming apart. One controlled tug and the liner started to come out fairly easily. It was quilted, so there was quite a bit of backing that flew around as I pulled it out. (I recommend wearing a dust mask if your sinuses are sensitive.)
It looks like there was a paper backing that didn't completely come off. I scraped some of it away with a paint scraper and then a wire brush and left the rest. It didn't cause any problems to leave it.
At first I thought I would keep the trim, but later decided to go for the gold and replace everything. (It really helped with the odor problem.) Some of the trim was cardboard backed and came out without much problem at all.
The one part of the original interior I DID keep was the pocket. I figured it was in good enough condition and would be useful in the display.