what is your height in your 4x4 i am looking at the HLG 260w xl QB v2 rspec kit if it works out will add another ... that way i will have a over lap prime light and i can keep the lights at the same height i have my hps my tent height is a concern so these lights will work but my math really sucks ... 

i try to keep it 18 in at a minimum but 24 seems to be my sweet spot.i have had some get up to 2 inches from the light because of stretch but it didn't seem to hurt them at all. i just dial them down a little. hope that helps