I built one . . .
This thread is about the 8, but many have looked at the tail-mate plans. 7 and 9 owners should be warned - the rudder cord is too long for the stock plans. Measure your tail wheel to aft rudder distance and modify the drawings accordingly. Also consider the mod that Sam made to his wooden shoe, that is to allow one to shove the shoe under the wheel without having it having to lift the wheel.
I made the tail-mate from the plans herein using 1/8" wall 1" tubing. It is plenty stiff, but the wheel base in both directions is the weakness to allow use as a working stand. There are lots of small details to change, so consider them like a vans print, a good suggestion, and prove to yourself what works.
1st Flight 1-27-18
Phase II 8-3-18