Sorry to interrupt this thread but may I ask where you bought the 83deg thermostat please? Also, my 103 engine heats severely after being shut down (from about 90 to 110) on occasions. Is this normal? B.I., did you say your aux fans run while your 300E is shut off?
'01 E430, Sport 72,000 mi
'98 C280, 126,500 mi