We've got a Grand Junction 35TMS that the black water waste valve has started leaking. I really don't want to pay over $100 an hour for the local dealer to fix it, so I'm hoping I can get some help. I'm pretty mechanically inclined, so ability isn't my fear. The problems that I am running into is that I haven't done anything on an RV before. It looks to me like I will have to remove the stuff on the belly of our rig to get to the offending valve. Does anyone know if I will have to remove all of it, just a small portion, etc? After that, what is the best way to get to the valve and remove it? It looks to me like the valves have a cable attached to the handle, but I'm not sure how long they are, or if I will even be able to find a replacement for it. Any help will be greatly appreciated.