Door jamb filler/ adhesive

I removed my windshield reveal moulding, from my 78, to clean up and replace the weatherstrip. While doing so, I noticed some rust at the lower windshield frame corner. This is where there are three pieces of metal spot welded together and is just above the fiberglass door jamb. The filler/adhesive was sponge like and breaking down. This was easily removed and cleaned up. What would be a good replacement for this matieral? Glass based epoxy? Some sort of flexible adhesive? Also, is there a torch spec for body mounts? I have 1 loose bolt.Thanks.

That sounds like seam sealer. It's fairly inexpensive. I don't think it's bonding adhesive, it doesn't deteriorate.

Thanks Dave, I will check an auto body supply shop. Ray