Sonex released a Service Bulletin for all Waiex, Waiex-B, Xenos, and Xenos-B Aircraft on 04.29.20, reference XNS-SB-003 showing cracking of the tailpost channel. Photo of issue:
https://www.sonexaircraft.com/documents/plan_sheets/Tail_Post_Channel_WIX-XNS-SB-003.jpg.Coincidentally, I found several weeks ago the rolled knuckle hinge rather than the extruded knuckle hinge had been used in this application. Removed the bottom skin around the tail wheel to better access the nuts on the back of the tailpost bolts. Removed the tailpost bolts and tailpost doubler. Removed solid rivets and hinge. Cut new MS20001P3 hinge and aligned it on tail post channel. Added this area to the preflight checklist inspection items in the POH.
Difficult to reach the nuts, will take a look at removing a little material from the tailwheel reinforcement angles to open room for my arm to fit through.