If the patches are already installed then GluVit for sure. I can attest to it's reliabitily for sealing these types of patches. If you've yet to apply the patches then a bead of 5200 between the surfaces is an excellent solution. 3M's website rates it good for this type of application. You would also follow that with Gluvit over the entire area with about 4 inches of overlap. This is what I did and I have no, none, nada, zilch, leaks. I almost feel like I wasted money on bilge pumps.What is the best material to waterproof riveted aluminum to aluminum patch panels on the bottom of the boat? I have some 3M 5200, but have heard it's not really for aluminum, and the patch is a little to big to consider jb weld.