my ubolt nuts as well as the stud nuts are all 15/16".
for the zero rates i'd bring a couple sockets for tightening the center pin and offset pin if you decide to do that. a pair of vicegrips for holding the pin in place while you tighten. something to cut the center pin down. big c-clamp for holding the leaves together while you drop the stock center pin out.
jack/jackstands for supporting the axle and truck independently. if you are offsetting the axle, you'll need to make sure that your ubolt plate is drilled or slotted to accomodate the new center pin location.
all i can think of at the moment.