Final work on the flap motor components today before we can move onto priming.
The last step is the installation of the F-785A backrest brace. You have to drill the #12 holes in the flanges of the backrest brace to receive the screws that hold the side covers in place.
To ensure positioning, draw a centerline on the flanges. My initial fitting didn't work quite well. I found that my holes would come out too much on the forward side of the brace so I decided to make a small spacer that would fit underneith the top of the brace between the brace and the F-705 bulkhead flange. I used a 0.064" piece of stock material and that solved the issue.
Both covers clecoed on to verify alignment.
On the top of the picture below, you can see the spacer between the brace and the bulkhead (top center of the image)
After drilling, the holes came out great. Don't put too much pressure on your drill bit when you use the side covers as a guide. These covers are flimsy and putting too much pressure might disform the holes.
Installed the one leg nutplates on F-767. I usually put a screw in with some washers to keep them in position.
I also drilled the nutplate ears for the F-680 teflon bearing block. One is a K1000-3 nutplate and the other an MS21051-L3 one leg plate nutplate. Same technique using a screw with washers to ensure the positioning while drilling. Once one hole is made,add an additional cleco.
All drilled. Note that the first hole on the one leg is pretty close to the border but the AN3 (the one that really counts) is dead center on the flange of the F705 bulkhead.
(update after rivetting: it's a non issue. the rivet will set just fine in the nutplate leg. you just may need a half size longer).