I would suggest making the wire harness-to-Logic device connector Poka-Yoke so that there's no question of manually aligning the ground wires downward.
We originally planned to ship with this in the last product release, but we had to cut this, and a hand full of other non-essential mechanical features when we started getting behind. We'll definitely keep it in mind for future products though!
Also, this is a duplicate suggestion, also found here: http://ideas.saleae.com/forums/214303-saleae-ideas/suggestions/5639327-the-wire-harness-should-be-keyed
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