Replacing the fridge fan with a triple
I see I'm not the only one who cannot stand the noisy stock refrigerator fan!
I ended up using three super-quiet computer fans in place of the original. Each fan has about a third the airflow of the original (and a third the current draw). But by spreading three fans across the entire space, I seem to get better airflow.
On our most recent really hot trip (90+ degrees), the refrigerator seemed to maintain a lower and more constant temperature.
As you can see in the picture, I used the original fan bracket and simply added short pieces of aluminum bar stock to connect the additional fans on either side.
And best of all, it is completely silent now!