My thought is that it would likely be either 1) a failed idea that fell into relative disuse, or 2) a project done using existing HBK chassis from the Brian Caches throughout the Pentagon worlds, updating and upgrading the Hunchbacks with modern tech, instead of the effort needed to have separate and obsolete tech on hand.
So, I thought version 2 would be more interesting from a fluff perspective, indeed with the HBK's being a relatively simple and easily repaired mech that literally they just wipe the old warrior out of the cockpit, patch it up and send it back out.
That being the case, I decided to do a version using Alex's update to the Hunchy.
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Mind you, it is just a quick doodle, pen on paper whilst I watched NCIS, but thought I'd toss it up, since I have no updates currently on my Nova's arms (got an idea, just haven't gotten them to satisfaction yet) and my Summoner re-design is a while from publishing yet.
Thoughts?