Sounds factory but I would not like anything charred
This is what I did to mine
The side and part of the back were there was fiberglass insulation , I replaced with 1” duct insulation from a HVAC company ( this gives you the R value without the paper backing)
Then anything near the vent of the refrigerator I also lined with fireproof cloth that plumbers use when they solder copper pipes
Then the top of the refrigerator vent to the outside which my was wood , I put in a radius piece of sheet metal for venting and fireproofing
You could open then upper louvre openings with a screwdriver a little for better airflow
I ended up making a larger opening louvre out of sheet metal and adding a larger cooling fan to back of the refrigerator
I also added a 12 volt waterproof fan to the inside of the refrigerator
With this set up , on a 106degree day I have no problem keeping the refrigerator at 34 degrees
