Paul is correct about the feet-inches-eighths-plus a sixteenth convention. This is a pretty standard boatbuilding notation.

There are a couple of other twists in the offset tables. One is that the dimensions are given for sections in an upside down position, which is the way the forms are set up on the strongback. See illustration 5-2 on page 54. The second is that, as someone else on this BBS has already suspected, the table of heights for the decks seems to have the rows for "sheer" and "profile" switched.

All this should become really obvious once you plot a couple of the station forms. If I get my drawing table cleared off before I move next week I'll try to confirm how the offset tables are set up.