OK, I just asked this question in the introduction section...starting off not paying attention to directions! So, I have a project here in an old tenement building in NYC. Two by two foot section rotted/rusted out of a ceiling (in a corner). Four or five feet beyond haven't fallen yet, but there is definitely water damage under the tin. The ceiling is heavily painted. The radiator above is now fixed, so the questions begin...what do I use to cut out the section that needs to be replaced? Can I just use sheetrock to bring the tin flush to the other tin over the plaster? How do I meet the seams cleanly, and what is the best way to attach the tin to the joists? Any help, suggestions would be much appreciated. Thanks, Karen