Finally get to break out the pretty gold anodized center spar sections! Everything here was pretty basic given that there was easy access to rivet components onto the spar. The only place it got a bit tight is in trying to tighten and torque the bolts for the bearing bracket. There's a screw head on the bolt, and not a lot of room to squeeze in there unless you have a stubby screwdriver.

Lastly for reaming the bolt holes for the rear spar brackets, I drilled a block of wood with the final size dimensions using a drill press and clamped it to the part as a guide to keep the reamer perpendicular.