Greg,

I have always been nervous about cutting into the surface with a tool of any kind, it seems to me that this would produce weak spots in the covering.

I have used the tape method explained above, however I now prefer the following:

1. Stick some masking tape on your wing with the edge on the panel line.

2. Apply a very thin smear of filler up against the edge of the tape.

3. Sand (I use fine wet & dry, used wet) to blend the filler into wing surface.

4. Remove the tape, to be left with a raised edge to your panel.

The picture shows the results on my Royal Bearcat.

Simon.