Next we install the Top Rear Spar Angle 6-ZU-1-3 reinforcement doubler inside the rear (spar) channel 6W7-2.
Below is a view of the angle inside the top rear channel (inboard, over the rear channel doubler 6-ZU-1-5 previously installed):

This angle doubler sits inside the top rear spar channel.

Steve first clamps the doubler into position, and then back-drills from the top, and clecos it into position.

Here Steve drills through the top rear spar angle doubler into position.

The angle doubler is made up of two halves that are spliced together in the middle.

Now the doubler is drilled and clecoed horizontally to the rear channel (viewed from the back):

Next, we install the Aileron Rod Hole Doubler 6-ZU-1-4 to the rear spar channel over the existing aileron rod hole.

We back-drill it to position and cut out the aileron rod hole to match:

Video clip: Installing the Top Rear Spar Angle doubler:

I've just heard from Doug and Lori Dugger of Quality Sport Planes (in Cloverdale, California) that they will host a free "Upgrade Workshop" during the upcoming November 20-22 weekend. This is one more way for Zodiac XL builders, owners, and pilots to get assistance with the new upgrades required for their aircraft. For more information, contact Quality Sport Planes. RSVP to (707) 894-4084. Thanks Lori and Doug for hosting this workshop!

Also, please make sure to check out and contribute to brother Mathieu's "Zenair Q&A"
This will help answer many of your questions.

Next, we'll install the aileron bellcrank support channel inside the wing.