The first thing I did was remove the vinyl from the bottom skin. I usually don’t comment on this, but it took forever to complete this task.
I match drilled the F-705J angles to the F-705F channel. As you can see in the picture, I used several clamps to ensure the angle was appropriately constrained in all directions. The plans say the angle need to be raised 1/8 inches above the channel. To achieve this gap, I used popsicle sticks as shims. It turns out the popsicle sticks are 1/16 thick.
Both channels look good. You can see the popsicle sticks controlling the gap distance.