[hartbraker]

In all honesty, I wouldn't weld the cowl area shut because then you have to worry about water collecting and/or lack of air movement depending on what you're talking about welding shut. If you're planning on using POR15, that stuff is crazy good about preventing rust and it sounds like you're meticulous enough to clean out any leaves that do end up down in the cowl. I'd leave that part alone if I were you, but that's just my opinion...