I agree with you 100%. Ive watched the z film close to 100 times today and I cannot see the man move into position and fire one bit.
Blevins' "rifleman" is in the same spot in each frame on most frames in the Z film. And it doesn't change. It's an artifact caused by a piece of gunk in Zapruder's camera.
You would not expect reflected images in the Z film to be present in the Bell because they were looking in very different directions. If you did see the same reflected image in both that would be possible evidence of fakery.
If You are going to proffer that there was a "piece of GUNK in Zapruder's camera" which produced this Image between the sprocket holes, You are essentially discrediting the Entire Zapruder Film. If the camera is unreliable due to "Gunk" in the camera, then the Images it produces are also Unreliable.
Do you really believe that, or can you not think of anything else to say? That image is in the same spot in every frame from the beginning of the film until the end. That is, from before the limousine first appears until after the limousine disappears underneath the triple overpass. How you or Blevins can think that it would be the reflection of something outside of the camera is simply beyond me.