I put the empennage fairing in place and tried to determine the best method to drill holes thru the fairing into the existing holes. I tried a strap duplicator, but it didn’t let the fairing sit flat enough on the HS skin. I finally taped a small penlight just inside the flange of the HS skin. This lit up the hole so that it was clearly visible thru the fairing. I held the fairing in place and drilled a #40 hole thru the forward hole in the fairing-worked just fine. Removed the fairing, penlight and moved to the other side. Went thru this exercise several times—got the first 2 holes done on each. I believe the remaining holes should be easier—may be able to set a light inside the cavity behind the HS front spar and drill the rest of the holes, and then move to the VS.
Small penlight taped inside flange
2nd hole drilled-you can see the light thru the fairing