Continued backrivetting on the left elevator.

The plans call for backrivetting the reinforcement plate on the left elevator.
All the AN426-3-3.5's are taped in place and the plate put over the rivets. It is a no-brainer to backrivet then the rivets on the steel plate.

Results from the front

 And frm the backside

Next, add the K1100-6 nutplates to the reinforcement plate. I did this using the pneumatic squeezer. You have to be carefull befault the spacing is thight for the squeezer in there. I used the rivetting longeron with no top set.

A cleco on the opposite side will help keep it in place as you set the first rivet. Make sure the manufactured head sits flush. 

The nutplates stick out a little and are visible over the border. This is normal. I have seen some people opn forums grind them down to be flush with the edge. I think it is not a good idea and I prefer to maintain full structural strength. Although it's shear strength and only to hold the trim motor.  If there is interference, I can still handle that next at assembly time.

Finished plate from top side

From bottom side