I don't see any harm in the way you did it...
But I've packed a lot of bearings by hand and I've never put them in the freezer. Nor have I ever seen any shop do this. Nor have I ever heard of this. I'm going out on a limb and saying you probably don't need to do this. ;-).
And although the petroleum companies will love you, if I understand correctly and you are packing the centers of the hubs with grease, you might as well just throw that grease in the trash.
There is an actual inch/pound torque setting for the spindle nut after the initial pre-load, but your hand tightening is probably just fine.
P.S. I have always washed the bearings off with solvent or carb cleaner and thoroughly dried them before packing them to remove any wax/rust inhibitor that may have been left on by the manufacturing process...
"I'm not a Mustang expert, but like so many others I play one on the VMF"
"How do you separate the truth from the cr@p spewn on the internet?"
Last edited by 2ndGen; 06-17-2011 at 02:32 PM.
Reason: Added P.S.