Stock used adhesive - both in the gutter to hold it in, & the corners were all glued together as well.
If you don't use adhesive in the gutter, then it will stick to the lid & pull out every time you open the front lid, eventually damaging the seal.
I'd recco using it, but make sure to clean & rust proof the gutter first with good primer/paint, if it's not been painted already.
Tom
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