Bill,

You being the paint guru here, what should I do next?

The three images show one of the wing panels after a coating of a bluish high-build sandable primer and then sanding. Since I knew I had some ridges where the sheets met, I used 80-grit paper on a long sanding bar and sanded with the grain (lengthwise).

The areas that the sanding didn't hit are pretty evident. My question is: Do I continue with the prime-and-sand until the primer fills the low spots, or do I apply filler to all the bluish areas and then prime-and-sand?

It didn't make much difference with the stab, since it's fairly small. But four panels like this could use up a lot of primer and/or filler.

Many thanks,
Richard