I went out to the garage this evening with the goal of getting the rudder done. It is done!
Bending the skins over the rudder counterbalance ending up being simple enough to do. Measure three times then start bending. The technique described in the plans worked well.
Marking and drilling the back of the tabs was a bit challenging. Lightly hammering the drill bit against the back of the skin didn’t leave a really obvious center so I also used a punch to get a clearer mark. Match drilling the holes, upsizing to a #19, deburring, and dimpling both skins, and countersinking the counterbalance weight all went well.
I chose to dimple the nut plates as the flange was too thin to countersink. I was able to dimple the nutplates without issue and the dimple dies were small enough to fit without modification.
I riveted both nutplates with the squeezer.
Success! No pillowing after the #8 screws were installed and no need to add a blind rivet.
Finishing up required setting the final 12 rivets on the forward part of the skins. One more completed part to put on the shelf for later assembly.
On to the horizontal stabilizer..