Hi folks,

Early year project is to replace all the head hoses and replace the PHII pump. My system currently runs from the head to the Y valve underneath the sink, and then out towards the hull, forward to the holding tank in the port V-berth. The deck fitting hose runs out from the holding tank, up to the deck fitting that looks to be behind a bulkhead or other wall. I can't make out how I would get to it for replacement - what's the usual process with this?

For the Y-Valve -> Holding Tank hose, would I just undo it from the Y-Valve, gorilla tape the new hose, and push it through up and out of the V-Berth?
For the Holding Tank -> Deck Fitting hose, how do I replace the hose at the Deck Fitting end?

Any other weird bends or things behind walls/bulkheads I'm going to have to look out for?