For the arrow I bought, I had to print the parts at 106% for the shaft to fit though the parts. I printed the 4 channel servo mount, but the PLA I have is too fragile for the dimensions on the part. I ended up cutting some scrap foamboard to fit in a triangle configuration starting at the front wing support, and mounted the servos in that. The elevator and rudder servos are on the sides, while the aileron servo is directly on top, below the wing. My plan is to go ahead and glue the wing onto the mounting struts, and maybe add the rubber bands for additional support. The plane is small enough that keeping the wing removable isn't really necessary for me. I'll take some photos when I get home this afternoon, and post them here.
I still need to finish the assembly. My plan is to not secure the wing supports until I have the rest of the plane assembled, and then settle on a final position for the wing by placing it for the best CG with the recommended battery.