If you have an older Ozpig and looking to upgrade your solid door to a vented door these instructions will help you remove the old door and fit a new one. Depending on which model of Ozpig you own, you will have 1 of 2 different types of hinge pin. Very old models will have a straight pin that slides in between the door hinge and the hinge lugs on the Ozpig body. To remove simply use a hammer and centre punch or thin screwdriver and tap the pin until it slides the whole way out, if it's rusty you may need to let some WD40 soak on it for a few hours. Newer series 1 Ozpigs will have a straight hinge pin with a circlip holding it on. At the bottom of the hinge pin there will be a little clip. By inserting a very small flat blade screwdriver into one of the slots in the clip you can pry it off. Then the pin will slide out. 

To fit the new door, line up the door hinge with the hinge lugs on the Ozpig body. Slide the hinge pin in from the top and fasten with the circlip. Loosen the hinge nuts on the front of the door hinge and align the door so there is an even gap all the way around between the door and the Ozpig body. Tighten the nuts and you're done.