Just wanted to share pictures of my newly installed gasket on my WSM 18.5 around the door and lid. I used the 1/2" wide 1/8" thick tape. So far the door looks like it seals pretty well and the lid feels great when you put it on and it feels like a cushion.
I also left a little opening on the lid so that i can squeeze a thermometer cable between and still allow the lid to sit flush with the rim.
Will let you guys know how it performs on the next smoke! Can't wait to try it out!