Remember to have the servos in the bottom of the wing. the 1/4 stock is to have something to attach the covering to. Use soft to med-soft wood for the 1/4 and it will sand easier, sand until it matches profile of wing. Plan servo location fore/aft around the spar locations. DO NOT cut the spars. Use extensions or y-harness as needed to get signals to servos. Make sure there is a path for the wiring to follow, plan this part out. This is where the wire guide tube would have been nice. They can come out thru a SMALL hole in the center of the wing TOP SIDE. Go slow and plan before you cut wood. Make cardboard templates and test fit things before committing to wood, faster and easier to work with. Just remember difference in thicknesses. Use wood glue to mount components, not CA or Gorilla. Not a rush. Accuracy, not speed.