I've had my 6500 for nearly 2 years now and I've never used a cone stand off to the side. I do have them for my Janome 6125 and 6019 though.
These are two cones I have on the back of my 6500. The cone on the right I just placed there to show the ones I use. The one on the left is one that's threaded through my machine now for piecing.
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This is the front of my machine with the cones placed on the back.
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