Replacing TR 60 Sand Filter and Multi Port

We are planning on replacing our 21 year old TR 60 Sand Filter this season along with the multi-Port. We have our pool covered for the winter. Plan on opening it in a couple of weeks. Would anyone have advise as to weather we should open it with the old filter to get it cleaned up and then replace the filter, sand and multi-port...or should we go ahead and replace the system first and then open. Looking for pros and cons from the pros:) Thanks for any advise.

Vinyl Liner, 23000 gallon, Salt System