I added two Refrigerator Vent Fans... install and pics

It's nice that those fans are shrouded. Most people use computer fans which are very inefficient unless they are installed in a bulkhead to keep the air from "short circuiting". Without a bulkhead or shroud, the low pressure area below the fan pulls the high pressure air from above the fan and most of what it does is "recycle".

Put those computer fans in a shroud or bulkhead for better efficiency.