Best mod for a frig in a slide is to mount a small cooling fan directly behind the top vent and let it run 24/7.
Since doing the above I can leave it set at 4 instead of 5 and it stays 36 easily and up to 38 when the temps approach 100.
When looking down from the upper vent look to see if there are voids around the two cooling fans. I packed insulation all around so the new fan I added would easily draw the air from the lower vent up and out the upper vent. This also helps when the factory fans kick in, it makes it so there is not a bunch of cavitation.