Hello, first post here and I am on mobile so sorry if this is the wrong location to post. I am getting ready to reroof my house and my current flashing is not likely savable. It is a giant mess of roofing tar. I went to the local Menards thinking all I needed was a 8"ID flashing and storm collar. However upon doing a test fit and more measuring i find out that my pipe is 11" OD vs what seems to be a standard 10" OD. It will not fit at all. I cant find any branding on the chimney as its all been painted, poorly. It appears to be triple wall and uninsulated. Does anyone have any ideas on a flashing i could buy for this? Im set to do the roof next week besides this