Solved. There is a screw on the fender side of the low seat lock assembly.
Remove that and the pieces separate out either side of the frame.
Had to put pliers to it (or woulda had ta remove fender, etc... forgive me padre).
See photo montage of low seat lock exploded and assembled. (oops, attachment failed security? wtf?)
So, Got 'er done. Which means...
I've got a low seat and lock assembly for sale. Removed from a '93 K75S. YMMV :2thumbup:
And am looking for one of them storage box things to set on top of the fuel injector brain.