I know that one. What's different about this one?
Two hulls, field by field: what both records say the same way, where they part, and what only one of them carries. Computed by comparing the records rather than written down, so it cannot claim a difference the ships do not have.
Pick a second ship to compare against.
Only the 93 charted hulls can be compared — an uncharted ship has nothing on file to compare against, and inventing the other half of the table is the one thing this will not do.