scepter 23 owner needs help

[scepter23]

Have a 23 scepter with the notched transom and factory gigantic fish well located in transom splash well. My idea was to seal this up with caulking to seal it off and keep the backwash water out and install the plug on the outside of transom to keep it from filling with sea water . My main concern if I seal this up and any water does migrate past caulking I will have no way of removing any water. Any ideas on the best way of handling this? This is my first season with this boat, first time going in the water.