You can do it like this, but....
after attaching the lanyards, it is hardly visible that you did the 'vertical' seizing.
Also: as the shrouds are far more playable that the Original stuff, puttin gthe whole thing at a ceratin amount of tension, tends to remove the little gap between the parts of the shroud.
But okay, mine is scale 1:100, so at larger scale it will probably visible.
But t's fun to do
The vertical throat seizing is not done differently from the 'normal' ones: make a small loop in the shroud, make the seizing, then insert the deadeye and fiddle around until it is at the correct height,
secure the seizing, and make a second (and third) one above the throat seizing.
Jan