Ahh...FINALLY something I have some helpful input for! :) I've done this a couple of times with a 55, sadly I haven't found a way to do it without clouding up the water at all.
What I did was get a bunch of 5g buckets from the local hardware store, I used plastic bowl to scoop the water out of my tank and pour it into the buckets. Once I got the bucket about 1/2 way full I started adding some of my live rock, and fish as they became available, until the tank was pretty much empty. The first time I did it, I scooped out all the sand too, but the second time I just left the sand and enough water to keep it wet in there.
Once I got everything to the new house, I simply did everything in reverse. I used the same bowl to scoop the water into the tank from the bucket, inevitably one of the buckets is going to end up being mostly water with little or no live rock in it, so I started with that one. Once I got enough water in there to cover a few pieces of live rock, I just placed a couple of pieces closely together and poured the rest of the water over them so that they took the brunt of the force from the water and it didn't stir up the sand too much. I don't think there's a way not to get a bit of clouding in the water, but it should all settle overnight.
I would try to add any fish/corals last so that they don't get bothered by the force of the water while you're adding it, or just use the bowl to re-add all the water if you're patient enough for that. If you have a pump, like from you're SUMP or something, with a bit of hose on it, you could also use that to move the water to and from your tank.
Hope this helps.
