So i recently removed my convertible top assembly i wanted to utilize the tray in the back for storage sense my S is my DD in the summer. I wanted to line it with something so whatever i put back there would stay put a little better rather than slide along the plastic tray and be all loud and annoying. I decided i was going to put the tray in and have a fabric on top of it. So i went to Walmart and bought a 72" x 32" felt sheet they have hanging in the craft section. I am warning you i am no master with fabric haha. once the hardtop goes on you wont really see it that much so i think this will have to do...

 

Good inexpensive job.