I started late in the day but managed to get a decent amount of work done on the center section. I started off with completing the nutplates on the top of the center section. I used NAS1097 rivets for these.
Next, I opened up all the holes for the fuel lines and brake lines.
I then broke the edges, scrubbed with scotchbrite, degrease, MEK and primed.
As I was waiting for the primer to dry, I made the F-904J spacers. They come pre-cut to nearly the perfect size back in the wing kit. Fortunately I had labelled their use previously and they were easy to dig out. I had chucked them in the drill press and polished them to proper size.
Easy peasy.