I have not done that route
but have carried my mast on deck
over twenty times going through the NY State Canals.
Make sure the crutches are sturdy and high enough to go over the dodger
(it always rains when carrying the mast on deck).
Besides lateral lashing make sure you secure the mast so that there can be no fore and aft movement when the boat pitches. I also leave the spreaders and rigging
on the mast. Just lash the shrouds together so you don't trip over them.
I leave my roller furling genoa
on the furler
, protects the foil and reduces storage
space. Just lash the works to the mast. Leave the main on the boom, again you don't need another sailbag to take up space. Stow the mast butt forward with a fender
lashed to the side in case you touch a lock wall. Also make sure your anchor locker
are not obstructed. You never know when you might need to anchor
Take care when going through a lock or going alongside. Remember you now have a 68 foot boat.