Started working on the wing root fairing on the left wing. Because both the fairing and the wing skin are pre-drilled the position of the fairing on the wing is pre-defined. The builder cannot do much adjusting. I assembled all the parts (tools, plate nuts, screws, etc) needed to do the job. Test fitted the fairing with clecos after which I de-burred the left fairing, pulled the protective plastic from the underside of the fairing and cleaned and deburred around the screw holes.