It is a little back-breaking but there's no need to stress. Beat 'em up a bit.
I usually pick a line a start by saying "Everything below this get cut, indiscriminately." Then, I have to remind myself out loud "INDISCRIMINATELY" every time I'm debating a cut. I take everything off of the main colas below that line and then I'll take all the running up those colas, leaving a few towards the top. After removing all the branches, it's pretty open and easier to trim the remaining fans.
Your situation, with the smashing, might be a little different. Granny could tell ya the better route, but I would would strip the shit out of them a couple days before the smash. Granny does a week, I believe, but these bitches recover so quickly in hydro. There's almost no slowing down. Strip 'em nearly bald, wait a couple days to smash, then wait a couple weeks to thin them out some more. Don't be afraid to take some nugget laden branches. The remaining nugs will grow fatter because of it.
My two cents. Let's see what
@CannaGranny has to say though. You've got some time to think about it.
I don't think it'd hurt to take a bunch of fans at this point, though. Like I said.. There's almost no slowing them down.