The mounting sleds for the Mk1 and Mk2 units are completely different, and are not interchangeable. It would be very difficult (if not impossible) to modify the Mk2 mount to accept the Mk1 chassis. For starters, the docking connector is completely different and mounted in a different location on the sled.

The person who sold you the Mk1 is probably making the same discovery right about now. Since he's got to remove that Mk1 mount in order to install his Mk2 anyway, I'll bet you could call him and get the mount from him.

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Tony Fabris