sounds like your in trouble. Six weeks of vegging (18/6 or 24/7) is too long unless you have limitless room and height. Your plants will at least double in height when put into flowering (12/12). I would cut it down to no more than 4 feet high, or bend it over and tie down with string. I think you may have too many in your cabinet too. It's always better to have fewer plants with room to grow rather than many plants crammed into a small area. You will get the same yield or better with fewer plants and adequate space.