Today I had planned to rivet these gussets into place.

But when I fitted the F-706-G brackets, I could see that there would be no way to buck these rivets through the longeron once the F-706-G is riveted in place.

Here's a wider view showing that three rivets would be obstructed.

While thinking that through, I decided to drill the remaining holes through the longeron and the gussets. One of the holes put a gouge in the top member of the F-706 bulkhead. Sigh...at least it'll be well hidden up in this corner.

I drilled the left side as well...

Then countersunk for a couple AN426AD4 rivets along the side. Looking at the plans, I can see why these are flush rivets (to allow clearance for the canopy frame), but I have no idea why Van's doesn't just make the two rivets behind it flush as well. Whatever, I guess I'll just go with AN470 rivets there like the plans say.

I took a few minutes to rivet on the F-707B clip onto the F-787 center stiffener. I had primed this clip yesterday while priming the countersinks.

I also dimpled and riveted the lower three rivets at the forward end of the F-787 stiffener. The top hole is kept open for future attachment of the canopy frame stiffener.

Soooo...after thinking about it for a while, I decided that in order to avoid obscured bucking by the F-706G (as mentioned above) I really need to rivet the forward top skin on now. But that means I've gotta rivet on the aft top skin as well. So I got the skins back out of the basement and clecoed 'em up.

I noticed that the forward side skin has a bit of a gap at both sides of the F-706 bulkhead just above the longeron. I think I'll make a shim to go in here.