Just went thru this with my 3.8 NA.

I was just over 99k miles and replaced the following:

Recommendation

- First thing to do is Flushed out Radiator and Engine prior to begining disassemble.
- Second is removing water pump and elblows and moving engine back-n-forth as hard
as you can to get as much antifreeze out of the LIM so antifreeze doesn't get into
engine oil area.

- LIM Gasket
- UIM Gasket
- Throttle Body Gasket
- Valve Cover and Grommets Gaskets
- 195 Degree Thermostat with Gasket
- Water Pump with Gasket
- Metal Elbows
- Heater Hoses
- Radiator Hoses
- Cleaned out UIM, LIM and Throttle Body

Last thing to do is oil change and add antifreeze.

Good Luck, George