check the archives
Bill,I need to replace mine too but don't know when. There has been discussion on the issue including how to and what sealing to use from folks who have done it. I agree with R.W. in that Rudy has supplied me with several pieces for my boat and I've been completely satisfied. I have one that is leaking a bit when it rains really hard. My frames don't look to be cracked anywhere and from what I remember of the archived discussions if you can remove the old ones without breaking anything you could then just replace the "glass" clean and reseal the frames and go. The full replacement ports are a bit pricey! Good Luck,Mike