The ailerons are pretty simple to build, so I'll just highlight a few things here. The Sonex-supplied tip ribs fit fine. Other builders reported needed to mess with these a whole bunch. Mine needed only minor tweaking around the very end to fit. I did put in an extra rivet top and bottom at the very end of the tip rib just for good measure.
Cutting the lead block for the counter-balances was a bear. What I ended up doing was using a saber saw and a very aggressive blade to cut it. I had to wax the blade constantly or it would jam up in the lead. I first tried to use my band saw, but it only made it about 1/3" in before it jammed the blade and stalled the motor.
When drilling the bolt holes through the lead, don't bother to pilot drill first. Go right to 3/16". Wax the blade well, use lots of pressure to make a big chip, and back the drill out every 1/4" to clear the flutes and re-wax. Other than being a bit on the slow side, this worked well.
NOTE: photos link to full size image