Thanks for the responses.
Ross, I suspect that since the Camlocs are wider than the Clecos, it might help a bit although I would be surprised if it were to take out all of the wave. I'll have to play with that idea some today and see what it does. The recess/step is sufficient (other than the "ridge" Jim and Tim noted) as noted when I apply light hand pressure along the edges.
Jim/Tim, the "ridge" is only on the port side. The "ridge" on the other side got trimmed off completely. I had less to trim on the port side due to making sure I kept a uniform gap at the prop spinner backing plate. The ridge will be sanded down once I get to that stage of cowl work, but is not really a factor in the waviness. I have the waviness on both sides. The holes were drilled with the cowl in place on the plane and align nicely. The upper cowl "out-of-the-box" has always splayed out relative to the lower cowl. It fits nicely with really light hand pressure, but the layup is thin enough that the "point loading" at the fasteners is creating the waviness. If the edges were thicker/stiffer or the cowling radii a bit tighter, the waves would not develop.