your going to have to get brute containers empty all the rocks, water and livestock. If you are using sand you can leave it in there with just enough water to cover it in the tank. Make sure all brute containers have a heater and a powerhead and proceed with moving your tank to a new stand
if you make sure all salinity, ph and temp is the same in all containers you should be fine. i moved a whole reef tank from an 80 gallon to a 120 gallon with 50% new water and sand over the course of 1 day with no deaths or problems.
When I switched stands on my 6' 150gal FOWLR. I pretty much did what tony said except I drained water to about 2" and slid the tank and old stand forward then slid the tank on to new stand.