I have a Whitfield P30 insert that needed a new door gasket. Tough to find the proper width gasket. Found a site listing a kit for 1 inch wide 7 feet long. Installed it and the door does not close. About an inch gap with latch pushed all the way in. What is the proper size? Is 1 inch too big? Had a lazy flame and the damper was not changing the sooty flame. Thoughts?