There are 2 clips in the aft lower cabin that seem to interfere with the installation of the seat. I'll reference the parts in the plans before explaining further:
WIX-F09, View F-F: Note the appearance of the clip on the -02 assembly reference (the part number for the clip is F10-08). It is illustrated here at full height, unmodified from the clip provided in the airframe kit.
Here is a picture of the installed clip in my fuselage:
WIX-F08, Detail B: The 1 1/4" distance between the hinge and the bottom corner of the seat sling creates interference with the top of the clip mentioned above. Here are some pictures that illustrate how there's no way the bottom of the seat can be 1 1/4" inch below the hinge without contacting the clip:
My assumption here is that the top of the clips need to be removed, but want to run it by Sonex and you all before doing so, since it's not in the plans.