Flexplate is not fits the torque converter

Hi
small update, looks like I have to close this thread. The flexplate (Magnum balanced, exactly I needed) installed but the vibration has not gone. Sparks replaced with the new ones, "old" new-previous ones replaced. Compression is the same in all 8 cylinders. Action plan - make more photo, shoot the video of the vibration, post another thread with the help needed.

why some sparks have the difference "color"? it's normal?
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