Sect 9-19, Step 3: LH & RH Elevator Skins top and bottom cleco'd together at Ribs...to blind rivet soon. Sect 9-20, Step 1-4: Get to try out RV10 Special Bucking Bar (borrowed from Terry Moushon, builder RV10 Thanks Terry !) After shimming to prevent any deformation of TE skin "reverse bends", used special bucking bar to rivet Rear Spar.
Instructions have you start with LH Elevator, since those are on bottom (any oops will be less visible). Good idea, but whole procedure was much easier than I'd feared. Just insured bar was correctly positioned for each rivet. Both LH and RH Elevators are A-OK.
Step 5-6: Blind riveted Top and Bottom Ribs to each other, joining Elevator into an assembly for Left, and one for Right. Sure was important to use extension handles on rivet tool ! I used cardboard under tool also, to prevent any "dings" to skins when each rivet "pops".