On the 63qt., there is no room to add a fan.
Mods I did were:
1) Open vents and install wire fan grills for better airflow.
2) Seal around fan with foam to force all air across condenser.
3) Seal vent panel under control panel with tape so air must travel over compressor
4) Reverse fan on AC power supply so air flows outward, promotes crossflow over compressor
5) Adjust AC powers supply voltage from 12V to 12.6V
6) Add reflective foam tape in compressor chamber to reflect heat away from cold areas.
Mods I did were:
1) Open vents and install wire fan grills for better airflow.
2) Seal around fan with foam to force all air across condenser.
3) Seal vent panel under control panel with tape so air must travel over compressor
4) Reverse fan on AC power supply so air flows outward, promotes crossflow over compressor
5) Adjust AC powers supply voltage from 12V to 12.6V
6) Add reflective foam tape in compressor chamber to reflect heat away from cold areas.