Cowl panel to firewall question

[TROUBLE987]

I'm getting ready to replace my cowl panel.The question I have is what are you guys putting between the welds like the factory had to seal the water from running of into the engine compartment?

[dougs bs23]

Honestly the way they rot out between the panels I don't think much of anything was there. So a couple coats of weld through primer attach them and try reaching through and apply seam sealer or after welding them together spray the inside area between cowl and firewall with a good coat or two of undercoating or spray on bedliner

[Topcat]

Epoxy metal bond would likely be the best way to go on the firewall seam.
You could replicate the look of the factory spot welds prior on a bench vise.

[mopardave]

tach weld here and ther but panel bonder is what i am going to use.

[johns cuda shop]

I think panel bonder there would be overkill, Lol.I dont think it would rot out if you use weld thru primer then weld. These cars didnt have anything and they lasted this long,Most of these cars are garaged kept and not parked under a tree. I would seal the area after you finish welding it .