Fabricated HS Attach Angles from aluminum angle stock. Precision is the key when constructing the bracket. Jacob made me focus on the precise location of the main pilot hole on the piece. When I drilled the nine holes in one unit, I matched drilled the other side after clamping to the table. Used clamps and clecos to attach to Spar, then match drilled holes through Bracket into Spar and Doublers.
