I have a Goodman air handler that is horizontally positioned in the attic. There is a secondary drip pan that extends below the whole unit. It is approximately 22' X 53" and looks like a custom sheet metal pan. Is there any way/where I can purchase a pan this size of any kind of material that will hold water? Or, will I have to cut some sheet metal myself? I have already contacted a parts company in the area (Lombard, Ill.) and they only had the small plastic pan that is contained inside the unit. HELP!!!!!! Any suggestions will be appreciated.