I emailed the FT guys and Fred recommended a thread so here you go. I built the "stock" Viggen a couple weeks ago. I flew it a couple times and it was a lot of fun. It needed some yaw control and when playing with it with Cody Wokcik we decided thrust vectoring would be cool. I went home and search my spare parts and came up with this. See photos. I had a TH micro digital servos that weigh next to nothing. There was room right below the Vert Stab. The vane is balsa with a sanded leading edge. I carefully inserted the push rod through the vane and used foam board and golden rod w hot glue to support the rod. I used a collar with a glued arm as linkage. Flight tests have been great. The control in hover is great, flat spins and zero airspeed turns all good too. At full throw it does make a lot of drag and some strange noise. You could probably get away with a smaller vane biased behind the pushrod (aft of the thrust tube). I will try to post videos when I can. The pics show the design.
