dakar leafs pack tundra dc. height gain

hello im planning to purchase dakars leafs packs 2.5 for my double cab. anyone here using theses on a double cab. do you get only 2.5 when installed or do you get more first and then after it settles months later is when goes down to 2.5. planning to get 3" total out these. i will purchase addicional leaf to add.5" if i have to.
will that be better or will be better to add cb +1 shackes(.625").
my bed stays empty. i do tow sometimes a boat to the beach, but do not offroad and my bed stays empty. i planning to get around 3 in lift.

thanks

 

OME tends to run on the higher side. Expect at least 2.5 lift, probably 2.75 or so once settled. Add a leaf will of course ride stiffer, I would opt for shackle for any more lift.