A new thermostat and hoses are going in this weekend. I'm also going to flush the system. It's a very clean Southern Florida car with only 75k original miles on the clock now. From what I have already observed the coolant system is clean.

The engine heats up during stop and go traffic/red lights.. I haven't seen it go above 100C while driving at a decent pace. I'll do more driving this afternoon to see how it reacts. It has not gone over 110C and certainly never over 120C on my watch.

Thanks once again for your help.