My concern was also the permanence of using it ....The fat mat is sticky enough to hold on to anything it touches, but don't think it should be used to glue things together? Once it's on, it's on, and it takes a LOT of elbow grease to remove it. As Rick said above, I would get a can of seam sealer from your local autoparts store.
I used this seam sealer in my car and am happy with the results. Has a thick consistency and sets up firm, would be perfect for building up between the bracing and lid to hold them away from one another: https://www.autozone.com/sandpaper-...n-gray-auto-seam-sealer-caulk-12oz/167027_0_0
It's light grey out of the tube and set up if you're worried about color.