This picture shows me using a rotary cutting tool to cut away part of the can holder that is interfering with the CO2 tank. You can also use a saw or a sharp box knife if you have strong hands
Note: A recent customer successfully converted his fridge with a 10# CO2 tank and a 2 pressure regulator. He cut out the entire center of the panel, leaving the panel screws & outside edge in place to hold the door gasket & put a small shelf across the ridge in the back. This let him place the 10# CO2 tank in the back, right corner of the fridge with the regulator set to the left. Cutting out the entire center of the door panel lets the kegs sit more towards the front & gives room to place the CO2 tank on a shelf.