The maramu that I updated (1989 #261) had copper tube imbeded in the glass and came out of the hull forward of the bulkhead and then went up under the head platform. I re-piped with pex and used hose clamps to connect to original pipe just after the bulkhead because I could not figure out how to get to the plumbing connection under the head for a home run. That eliminated the leak but I lost the boat before having a chance to go back and complete the job properly. It's been a few years so memory is a little fuzzy. Hopefully someone else can help further.
ALSO ... while you are looking around that area... Joel told me to check for wood rot under that spot that he noticed in other older Maramus of that era where the water collected. Good luck and have fun with your Maramu!!!
Ross in ny
Sent from my Verizon, Samsung Galaxy smartphone