Cycling "new" tank

[Treebeard]

I am trying to determine the best way of moving from our old 46 gallon to a new 90 gallon tank. I have about 20 gallons in the sump, but it will probably hold close to 45 gallons. Do I have to cycle the new tank before I move the livestock over if I use the old water and live rock? I am also planning on adding more live rock to the sump before I set up the new tank.