Most hatches have anodized
aluminum frames, with
Acrylic (Plexiglass™) or Polycarbonate (Lexan™) glazing (not glass), for which a mediun or hi-modulus
neutral curing silicone sealant, such as Dow Corning 795, (NOT acetoxy* cure) is usually recommended.
You should probably seek specific recommendations (performance & compatibility) from your glazing supplier.
* If acetal cure (oxime) type silicone base sealant is used, the emitted gas causes
corrosion & cracking (in plastics).
If your replacement glazing is actually glass, I'd recomment either a polysufide or apolyurethane
adhesive sealant.