I am about to do the same thing sort of..... I am moving my 120g, however im moving it into a 168g
This is my 2nd time moving my SW tank. This is my plan. Im going to have the new tank about 1/3 full and 2 garbage cans of pre mixed water ready to go. I have lots of old salt buckets so i will transport my fish in the buckets (1 in each bucket 3/4 full of water) all my rock will be going into 2 other garbage cans with as much water as i can get in them. I got some styrofoam boxes from the LFS to put my coral's/nem into.
Talk to your LFS and see what they have for containers that you can borrow or have, and keep as much water as you can. Try not to stir up your substrate, add new if you have to. Try to get your friends that have some knowledge of SW or at least if they have moved a FW tank before that should help you in the panic. Definitely dedicate the whole day to do it. Hope this helps you.