We TIG weld in our conversion flanges with a butt-weld, but you can also fit them under the existing panels as shown here and tack them in with a MIG – that is what most of our customers do. Note that we always cut the headlamp hole back 1/4″ to place our weld 1/4″ back from the flange – we have a pattern for this. On your car, you would have the edge of the headlamp hole almost right up against the stepped edge. Also note in this photo that the hole was cut very sloppily at the factory, and while we have cut metal back along most of this hole, we actually need to ADD some in this location!