Pretty straightforward to cleco the side skins and the aft bulkhead to the nascent tail section. The confusing part is interpreting the instructions because it never explicitly states to rivet the lower skins to the frames. I later made a call to Van's and confirmed that it's OK to do so, but it threw me off a bit. (The instructions tell you to mask off the holes in the forward 7" for later use in joining the tailcone to the fuselage, and to "rivet the open holes" of the skins. Every other place in the instructions, they explicitly state which parts are being riveted together, so I was a bit confused.)
The strings on the left are going to be used to pull the stabilator control cables. The coiled white cord on the right is the wire bundle to the trim motor.
And here's the aft view where you can more easily see the string for the stabilator and the trim control cable. Note also the veritable hornet's nest of clecos on the aft end where the side skins will be riveted to the aft bulkhead. Lots of strength needed back there!