I installed an additional rib in rear fuselarge of my 360. see pic

What tailstiffener did you mean?

 

 

Christian,

 

A few have completed the tail cone - that is the strake starting the vertical stab was considered weak so a " closeout rib" was placed horizontally at the base of the strake (the horizontal line I added to your picture below.

 

 

Did you feel your tail was stiffer?  Are you going to be at OSH this year?  I would like to bend your ear (and your tail).