inner cowl panel? weld in or epoxy?

[cdub2010]

I finally finished welding up the inner cowl damage on my 70 gmc. I have the new inner cowl fitted up and ready to go. Should I drill it full of holes and plug weld it or should I use panel bonding adhesive, if so any tips or advise what brand?

I'm leaning to panel bond for a few reasons, ease of use and waters tightness. I have become a better welded lately, so much so that now only 85% my welds looks like Fido's butt.

Should I use body filler over my welds to smooth them out or just use a seam sealer and call it good. Do I need to prime before filler or just add filler right over bare metal. I have attached a picture of my current progress.