Hi Gary
Give some thought to installing a Valtera internal fridge fan to circulate the air inside the fridge as well. Ebay, around $40 and the best money to spend. Simply velcro onto the bottom shelf, powered by two "D" batteries. We have actually dropped the temperature back a bit since installing one and it stops a lot of the condensation on the rear wall of the fridge. (Waeco/Dometic)
http://www.ebay.com.au/itm/Valterra-Fridge-Cool-Fan-Airator-Caravan-Camper-4WD-Camping-RV-Motorhome-New-/321904135709?hash=item4af2fb4e1d:g:8L0AAOSwHMJYEWB5
Cheers
Merv