First, attaching the skins to the frame.

Matchdrilling all the remaining holes to the spars.

Trimming material from the R-710 horn brace according to the plans.

I read from a collegue builder website that he had to re-order this as he cut away too much and didn't respect the min edge distance needing a reorder of the part.
With this in the back of my head, I started real carefull on this part.
To make sure, I first made a 1 on 1 zoom copy of the plan to full size and cut it out. I bend the paper and installed it in place just a the real part would do. Then marked the positions of the holes through the R904 bottom rib.

Don't get seduced to draw a line on the pre-punched hole in the piece and cut away all because you will cut away too much.

After measuring, glued the paper mock-up on the real part and then used the snips and grinder to remove the excess material.

The result is really a nice fit.. Then drill #30 the flanges to the spar and R405PD. In the picture below, through the lightening hole, you can see the nice fit to the spar.

Then use the skin to drill through the R710 rudder horn. I should not have drilled these holes during matchdrilling skin. But didn't enlarge the holes bij drilling second time.

As last work of the day, made the R918 bottom attach strip. Noticed that there was a little bump marking in the scratch material as delivered by Vans. This is a low risk area so I assume it's not crucial.These plates are used to attach the rudder fiberglass bottom.