Triangulation linkage kits explained - MaslowCNC/Mechanics GitHub Wiki
From this discussion -
https://forums.maslowcnc.com/t/triangulation-linkage-kits-explained/2736
Link to the document:
https://www.evernote.com/l/AkVPAdcpoR9NnatdCZ3vSZfw32mK2Tw2yIE
as of 3/15/2018 the Ring Kit is included and was added to the assembly instructions.