Pat, you're definitely fortunate to have guys like Doug and Bill help you out.
When I screwed up the door opening on the passenger side of my truck, making the door gap too close, rather than cut on the cab, I ground the door edge back and welded it closed. I thought that approach was better than cutting the cab panels. In the case of your passenger side cowl, I don't know of a replacement that doesn't have the vent louvers. Cutting back the door edge there would have been a better choice than cutting the cowl at the louvers, but it looks like that's a done deal. I agree that the louvers will get warped when that cut is welded back up. I only replaced the lower portion of the outer cowl there and retained the original louvers.
Looks like it's fortunate there's an access opening behind that 5/16 bolt to get a nut on it. But I think I would have spent a few minutes grinding the slot in the hinge arm to fit the original size bolt into the captive nut.
Moral of the story - Pay close attention to the original door opening dimensions.
