Vance you can get high temp. sealer at an auto parts shop . It will be in a squeeze tube.
Sand down your Sm0kers edge around the openings (fire box and the cooking chamber) enough for the sealer to stick to the pit .
Now , squeeze the sealer around the edge of the openings , place some Saran wrap over that and shut the doors. Let this sit for 24hr. , the, peel the Saran off.
You should have a really good seal and if needed , you can use a razor blade to cut it off to re-pair or re-do it if needed .
Hope this clears things a bit. need more help
, PM me .
Have fun and . . .