I guess in light of the camera being set on tripod, it's also conceivable that the blast pressure could have moved camera enough to distort the image.
Decided to briefly afix the part of sight door track that goes aginst shield itself. I wanted to be absolutely sure I had filed the correct amount for door to sit nicely against it. Then measured the minimum distance I can overlap the top piece to the door, and what do ya know, I won't need to shave any more metal off the width. May thin the thickness about 0.5mm once the welding has been done. Welding will be about a two minute job, literally.
Incidentally, the part sitting on upper shield in first photo, is laying face down, so it's bass ackwards! Left is right, and right will be left.