When I replaced the fill and vent hoses on my Tsunami,I figured that it would be a nightmare.
The opposite was true.After I pulled the hatch cover,cleaned,inspected,and re-installed the tank,it was just a matter of connecting the new hoses to the old,with a a piece of tube and some hose clamps,and pulling them through.
I removed the fill port,and pulled the old hose,and new hose out from the tank,under the deck,and up the pillar,to the gunwale as one piece.Discarded the old hose,cut the new hose to length,and attached it to the fill port,and tank and re-installed it.Did the same with the vent hose.
Other than a little bit of a PIA getting at the screws,it was pretty easy.