External fans for Norcold fridge

They are on the same snap disk sensor that controlled the original "computer" fans. They just did not do the job. Generally they do not come on unless we are driving down the road so the engine provides the power. If we are going to be parked somewhere it's so hot it would trigger the fans, we'll be somewhere with hookups so we can run the AC for us. We generally restrict our dry camping to the spring and fall as we are not fans of having to run a generator to be comfortable. I think vehicle motion interferes with air being able to circulate into the vents. Do they even make 10" computer fans? The two "frame" bars are 26". Enough to span the opening with enough extra to reach the 3/4" wood strips I liquid nailed to the inside surface of the exterior wall (nothing in it but foam to attach to).