"Real pain to do?" Nope. Second set of hands was very helpful, though.
You have a jack as a floor jack?
BIG c-clamps are good...
One note...before you tighten the bolt to put all the leaves together, make sure that those two Calmini leaves are put in between evenly. I can't remember if each side has different length from the center (bolt hole), but leaves line up right when they are put together. ....like each end, leaves goes longer and longer (shortest, shorter, medium length, longer, longest.) Man, it's hard to explain...