A case laminate is printed on one sheet that wraps a stiff board. At the outer edge the sheet folds inside the book and is never seen again. Beside the spine it creases into a groove — the channel the cover swings open on.
Widths to scale for a 5.5 × 8.5 hardcover. The board and the darker groove beside it are both cover your reader sees — 5.70″ of it, a little wider than your 5.5″ page, because the board overhangs your pages at the outer edge.
So the middle of your cover is not the middle of your page. Your text was placed on the page, and would have printed 0.10″ off-center toward the spine. We've moved it onto the cover instead.
Only your case laminate changes. Your paperback and dust jacket are untouched.
A cover is chosen at thumbnail size and only admired at full size. If the title doesn't read here, it won't be read at all.
How it looks
Ask three questions. Can you read the title without leaning in? Can you tell the genre? Does one thing dominate — or does it dissolve? If the grayscale panel loses the title, you're relying on color contrast rather than light-versus-dark, and it will fail here and in print. More on the thumbnail test →