Hi chrissy, if you use the search button and type in the words "replacing fixed seating" at least four threads discussing this are already in the forum, there aren't many topics we haven't covered at some time. The search facility will help you find answers, if not start a new thread by all means.
As we have several already running on this subject I'll close this one, that way all the information will be kept within fewer threads, making it much easier to find.
If yiu need any help let us know.
Angela B