Hello I will help you with your question
Remove the coils
NOTE: This engine has aluminum cylinder heads. Do not remove the spark plugs from a hot engine, allow it to cool first. Removing the spark plugs from a hot engine may cause spark plug thread damage or cylinder head damage.
You have special plugs in this engine replace with only
SPARK PLUG TYPE GM P/N 12569190A/C DELCO P/N 41-981
Let me know if you have questions