You would think that updrilling this small amount of structure would be quick and simple...hardly. There is A LOT of material stacked up here with the incorporation of the service bulletin doubler strap. The strap is thicker than the main Y structure. In some places, there are as many as five layers of material to drill through. Also, some 6" drill bits would have come in handy for this job.
It took a little time and I had to dig out my old pull-type clecos so that could clamp the stackup together.
I deburred, cleaned, and sprayed on a good coating of primer to finish off the night. Assembly is next!
