Yes, what is it you want to know?
Have they got too big? or thin at the bottom? or something else
I think I'd get the height down first and maybe do one side . Though beech may be happy if you do the lot. I haven't tried.
take the top down and the side facing your house, they'll regrow quickly this year. Then next winter do the opposite side.
When taking the sides back, cut back to about 4 - 5 inches from the main stem and it'll resprout
...and cut it to a foot or so below where you eventually want the top, to allow it to grow.