If you are really worried about the engine temperature, you can always shortcut the auxiliary fans so that they run 24/7...
Since my dash cluster doesn't support the temperature controlled auxiliary fans for the airco I retrofitted in my car and I am in the progress of getting the 96 C36 AMG dash cluster functioning in my 93 C250D, my auxiliary fans run constantly during the summer (AC on) and never run in the winter (I remove the fuse).
I don't like this situation that much, but the temperature is very constant whether I am driving or standing, whether the car is cooling or heating the interior...
Did you already receive the license plate frame?
with a minor 600+k