Need advice for BIIIIIIIG Plants

Okay, so I posted in my grow log about these girls.

They were vegged for way too long. I didn't get my setup done in time so they just sat there, and sat there, and sat there, and sat there....

They're huge. Too huge... Nice big healthy girls though.

My question is, can I top them? cut em back a bit? how can I do this without killing them? my light is as high as it'll go, and they're only maybe 6" from the light:

http://i1003.photobucket.com/albums/...e063Medium.jpg

How far down can i chop off their heads? What do I look for?

I've looked for a few tutorials and other info, but never seen anyone try it with plants this big. I need to kick these over to 12/12 asap...

Please help :(

this is not advice!...it's just what I do. I just crack the main stem over...and then leave it alone....it will still grow....
sometimes making a U-turn back toward the light...:thumbsup:

from what I've read, heard, observed, you could LST them, water them first, some say wait a day others say wait a hour, bend her stalk. it might be rough but then again, this is not advice.

apparently the forum doesn't like posting clickable thumbnails either lol

here's the bigger picture:

http://i1003.photobucket.com/albums/...e063Medium.jpg

Guess I shoulda tested that link :p

I read a really good article earlier on that whole, snapping the stalk idea... Didn't know if I could try it with these girls... but I guess as big as they are I gotta do something.

I'll kepp y'all posted :p

those are looking good. lol Yea I let mine veg 2 months now I have 6 4 ft plants taking up way too much room

if i were you i would take the four biggest branches and bend them at a 90 degree angle until it snaps. This will make everything grow toward the light and create a shorter plant. While i usually do it in the veg state, i do it sometimes in flower when i run out of height(the same problem your having. ), just dont do it too late into flower. It stresses the the plant and can reduce yield and qaulity. If i were in your situation id'e bend and supercrop.