Replace the rear lockers with the 750's. They won't fill completely because of compartment constraints, but you'll get 650-700 out of them. Replace the center with the 1100 sac, again, won't get completely full, but certainly close enough.
When setting up for surfing;
Fill Center sac
Fill surf side rear sac (leave opposite side empty)
Fill the 600 (old center sac) on surf side seats and partially on sun pad
PP set to 10.7-11.2
Wakeplate @ 50% and raise as needed to cleanup wave
My 05' Launch 22ssv