It is not really that big a deal. I created my own leak last year when replacing the control board. The mounting holes were in different spots and I put a screw through the tank. A screw hols is a quick easy repair on an aluminum tank, no way in heck was I going to pay nearly $300 on a new unit. Welding shop quoted me $25 to patch a hole, a crack may be a little more. The one pictured above however is toast. I think the clamp rings were $10
The parts on the pan all unscrew, and the clamp rings holding the pan on the tank are one time use. You don't try to remove them, you cut them off with snips or a dremmel. New clamp rings can be had at most rv supply houses and are not that expensive. Installing the clamp rings is not that hard either. I used a large screwdriver and hammer and gently worked side to side till they were in place.