Changed water pump ,thermostat ,flushed heater core
Did you purge the air out of the cooling system? and make sure the fan is working.
Double check what type of thermostat you bought sometimes if you get the wrong thermostat you will get the wrong temperature reading.
Looking for a Used S-Series in your area?
CarGurus has 615 nationwide S-Series listings and the tools to find you a great deal.
Search Saturn S-Series Questions
Saturn S-Series Experts
Related Models For Sale
Used Cars For Sale