In the overhead photo, Theodore Roosevelt is centered in the dock, so it must be a relatively early photo. At some point after the Ethan Allens and later classes came online, the dock was refitted with two rows of keel blocks to handle all the different classes, without needing to rearrange the blocks in between subs. Just based on length, I surmise that one set was for the GW class, and the other set handled all the later classes. The differences between the later ones could probably have been handled by stacking different amounts of wooden blocks on top of the steel supports.
The Takom kit includes two cranes, whose bases straddle the width of the wall. It may be that the original cranes were simply relocated to the outer edge of the wider top deck. Or if they are larger cranes, that may be a detail I'm willing to overlook
