Depends on ur time fella....if u want to keep to shirt vegging time I would put some nails in walls and put screen right below cfls....lots to go on so here bear with me.
Ok first with cfls below screen u wont need to lollypop but may suffer from burn as not much space between cfls.
The plants will reach that screen but at least another three weeks veg.
hps will make plant stretch when first flipped to 12/12 but having cfls so close may counter that a little.
what I would do personally....
higher cfl bar by 4 inches lower net to current cfl position and train plant to grow infront and behind cfl bar so the gap in the middle is occupied by the cfl light providing lighting to lower reaches and allow hps to take care of tops.