Ah that's a whoooole 'nother ball game Tom! You don’t want to mess with mold in the rafters or the ceiling. You have to use bleach and warm water on the rafters to clean them off because they are in the roof you don’t really need to worry about bleach staining the wood. With sheet rock or whatever you may call it, you can’t do anything to it if it gets to soak through. The best thing you can do is cut away the moldy sections and replace it with new. We ran into this with our ceiling and it was awful.
I had to cut out a 6’ by 10’ section of our ceiling to get all of it and it’s a pain because the boards come in 4’ by 8’ sections so that was fun lol. With your roof do you have proper ventilation so that air can breathe and it not get trapped?
As for the vinegar, that stuff is amazing! It’s got so many uses in the home. We haven’t needed to clean off rust from anything but we use it to clean all kinds of stuff like the washing machine, carpet stains, hard water stains in the shower and so many others. We have a gallon jug in ur cabinet at all times lol.