[JRTJH]

Several things to consider:

1. Before the mod to install, the trailer exterior wall provided insulation for the coach interior. Now, with "two huge holes for venting" there is no insulation along the sidewall of the new refrigerator enclosure.

2. During the winter, cold air will infiltrate that space beside the refrigerator and radiate through the 1/8" luan sheeting. During the summer, heat will infiltrate the same space.

3. You're going to have a significant "winter condensation problem" with that "cold sidewall on the cabinet"... And, it's going to be a "source of overly warm temps during the summer"...

4. Insulating the space is one way to negate the outside air infiltration, another is to seal the back corners of the refrigerator so the outside air can't get into the space.

5. You don't want to block the airflow along the rear of the refrigerator, but there is the "same outside air at the top of the refrigerator.

6. The entire refrigerator cabinet space, around the refrigerator, on the sides, the top and the bottom, should be sealed so nothing behind the unit can "migrate" into the living space. Both "raw, unburned propane" as well as CO from the burner can conceiveably enter the cabinet, so sealing that space so all the heat as well as burner gasses are prevented from getting into your coach cabin is an important consideration.

I'd look at using 1" rigid foam board, cut to size and wedged into the spaces at the rear sides and top of the refrigerator and then sealing that "in place" with aluminum duct tape or a caulking sealant that remains pliable so towing vibrations don't pull the sealant away from the edges.