Hey all....Its time to replace the faded, crappy looking convertable top on my 91. Mine (I think like everyone elses) is the StayFast cloth with the sewn in rear window. But I have seen ones offered with StayFast and a zippered/ removable rear window. Really considering this because if the plastic rear window gets damaged, scratched to hell, whatever, I can just order the window and zip it in myself. ANyone else have this and is there a concern for rust on the zipper?