moving the rear hanger and going to a longer shackly will not always gain you up travel, but will gain you down travel.
If you have checked shocks to make sure they are not limiting what i would try first is to remove the overload and the shortest leaf in the pack and put it back together and see how it flexes. if you lost ride height you can make new shackles slightly longer to get the height back but dont go too far. with the shackle mounted like yours and most toyotas the longer the shackle the more side to side movement it allows and the looser the truck will handle on the road.
worst case you dont like it you can always throw the leaf packs back in and go back to the old shackles. pretty cheap experiment.
