A pillar door Door Plates Stripped

[Gib74]

I'm sure this question has been asked a zillion time. I had two of the upper A pillar door hinge plate stripped out. I installed some keensert's tonight and one of them ended up blowing thru and falling down into the a pillar abysses. I think I was dealing with some unforeseeable rust, and it ended up breaking away. So now I'm left with a huge hole where my hinge bolt should thread into my A pillar door plate. So, the million-dollar question is where is the best way to access the threaded plate so I can get it out and weld some nuts on it or does anyone sell the actual threaded plate to replace? Do I go interior on the kick plate and then it looks like I gotta cut another hole to get into the abyss. Or do I cut on the exterior a pillar above or below. I can weld and fabricate fairly decently so I'm not worried about cutting everything up and not get it cleaned up. Just looking for the easiest and most efficient way to get into this thing. Thanks Fellas!!!!!!