The fabric panel on the back of my rear seat back has come off, and I can't for the life of me figure out how to get it back on. Seems as though it's just held on by the tension of the seat back cushion, but I don't see any way to relieve that tension to tuck the panel back in. Anyone know how to remove the seat back cushion? Or alternately, how to replace that back panel without removing the cushion? I'm hoping it can be done without removing the whole seat back. BTW, it's a 2010 C30 T5.