Black tank valve replacement

Sorry I have not responded sooner but I wanted to make sure the job was complete. It is I think but it was not the easiest repair job. I did have to cut the down pipe and use a slip coupling. But cutting the pipe was my last resort, so I thought. At one time I had all 3 valves taken out thinking maybe I could put the valves back in an order that worked. But like TXiceman mentioned the manufacturers leave no slack for replacement, and after taking it all apart and listening to my rv dealer, yes there is no room for replacement. This is a long story but I won't bore anyone with it. However, I have a good rapport with the service staff at the dealer I do business with and this service guy told me how to do this. Take a ratchet strap and hook it on the cross brace that the tank hangs on, then circle it around the tank, continue by the tank opening and keep going around the other side of the tank and hook your ratchet to the cross brace on the other side of the tank. Then start ratcheting, you only need maybe 1/2 inch but I was concerned about cracking the tank. I was assured it would be ok, and it was but let me tell you this did seem a little crazy. I was worried about the plumming going up to the stool and sink because they also had a pipe coming down from the bathroom sink too. Anyway I did get it ratcheted enough to replace the valve but it was very tiring and frustrating at times. This was my first valve replacement (and hope my last) but I don't know if the non-cable valve systems are any easier to replace. My guess is that they are not! JMO. Thanks again to all who contributed suggestions as it was helpful! Bill