This evening I was able to get the top and bottom skins riveted to the rear spars, rivet the rib halves together (blind rivets), and rivet the ribs to the front spars (also blind rivets).
Would you believe that I had exactly the number of LP 4-3 blind rivets that I needed. I hope there isn't anything else that requires them in the empennage kit... :-)
Anyway, with the pneumatic blind rivet squeezer, the blind rivets go by very quickly.
At this point, the next step is to rivet the skins to the front spar, which I should be able to do with the pneumatic squeezer.