[masraum]

I suspect I know the answer, but I want to check.

If you had 2 1"x12" pine boards glued together to give you a thicker board, and then you were going to glue another 2"x1" board to the long edge of the boards.

If the 2 boards weren't perfectly straight before gluing so that after gluing, the long edge is not quite perfect, what would you do to the edge to get the edge to be flat as if it was a single 1.5" thick board, sand, hand plane, something else?

And by hand planer, I meant the old fashioned kind, but I now see that there are power units available. I recently discovered that there's a Harbor Freight store about 3 miles from the house. I've been looking for an excuse to go. A small hand-held power planer for $50 sounds like it might be a decent option.