Rear Heater Hose

[fredb38]

2006 Jayco Travel Trailer
Jay Feather EXP 19H
Just bought a used Jay Feather. Found many little problems that I am fixing one by one. This problem started when I tried to pull the power cord out and it was hung up on something inside the storage area. I removed the plastic cover the cord goes through so I could get my hand inside. I found that piece of 1/8" plywood that should have been fastened to the bottom of the storage area had come loose and the cord wrapped around it. I have found the flexible heater hose going to the very back heater vent is broken. Also I have no power to the Left tail light and left rear clearance light. I feel all the problems are in the same area where the heater hose is broken. I need to get into the box area where the sewer hose, power cord, etc is stored.Before I start taking things apart is their a proper way to get into that box area? I can cut an access hole from the inside but no sure that is the way to go. Has anybody been in that area and if so how did you get to it?