Not to disagree with infomanpa, but I'd just read Laino and use his maps. Maybe check back with Gottfried for backup. I love Gottfried's book "Brigades of Gettysburg" but Laino has him absolutely beat on maps.
Correct me if I'm wrong, but my sense is Laino is a Gettysburg specialist, while Gottfried is a Civil War generalist. Nothing wrong with either one, but beware. My guess is that if you get down and dirty and start comparing maps you'll come away feeling Laino is more detailed and more accurate.
Both are good, but Laino's maps are better. Nothing can beat Gottfried's "Brigades of Gettysburg", but it's print and there are no maps.
OTOH, if you want something to read, read Coddington. <g>