The grey tank valve on our RW355 toy hauler has snapped off at the blade valve. I stopped by the local RV repair shop (that doesn't accept Good Sam extended warranty). How do I go about installing the new 72 inch pull line and handle and how do I access the blade valve to make the connection since the bottom of the RV is seal as we have the arctic/all season package. Do I cut the insulation and reseal with silver metal duct tape (as used for HVAC work). Thank you kindly in advance for any advice on how to do this.