plants look like they are in good shape, eh?
So, i'd suggest HST. just snap all of the colas a safe distance from light. they will heal within a couple days, if not 24 hours. try to only apply enough force to get it horizontal and least amount of damage to vascular tissue as possible. some droopage is expected but not always. support it so that it doesn't dangle freely, but it'll be trying to grow vertically again soon -- you my need to tie it down in future.
this can give you plenty of space. the buds will still develop fine. If the plant is still exhibiting remnants of vege growth, take that into consideration so you don't have to do this process twice.
consider the direction you'll spread it out.. try to break it down toward less dense areas of canopy, if possibly. make sure you don't paint yourself into a corner where one cannot easily be broken down without causing congestion - since you hvae to do it to large portion of canopy.