Were I to do it over again, the cooler doubler would have been moved outboard so the edge of the doubler matched the edge of the corner. Mine is about 1/8 from tyhe actual corner. That made some prepunched holes for another doubler part not line up. The doubler was prepunched and I drilled through that into the back baffle. Then there is another doubler that rivets to those holes but it did not line up, causing me to have an additional 4 holes drilled into that piece. To fix, I added a riveting strip on top of that doubler flange, drilled correctly. All is good. I used two pull rivets. One in a very tight corner and another to secure one end of a nut plate. Re painted the whole corner after all riveting was done.
The holes above the oil cooler don't match the doubler that goes there. I made a backing strip to fix.
Once all riveted together, I repainted it. Gets scratched during riveting/fitting.
That box on top of cooler opening is another doubler that used a backing strip to rivet correct holes.
