Did you decide against the rolling cover? What brand is the folding top? I have a spray liner in my truck but my business partner has a drop-in and they did have to cut it a bit to get the fit right for his Retrax cover. Does your cover use a clamping system that fastens to the rails? If not what?
"Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did do. So throw off the bowlines, sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover."- Mark Twain