Thanks for the replys. I ended up going to Tractor suppy. There were several temp. Rated silicon products. I purchased one for about 8:00$. , rated 600 deg. They had some for 650 deg. @ 2400:$. I removed the old rope, used a disc hinder to clean out the channel, ran a 3/16 bead all around and the placed the fiberglass rope in without stretching it, I then caulked to completely cover , then floated it off level, let it set 24 hrs. Thought I was not going to be able to get the door closed , used a cheater pipe to force it Let it set one day then built a fire. The door and seal has since seated so that I can closed it and, it is sealed really well. Next time I would stretch the rope just a little.