Hey there Harry, To control for space, the best is supercropping, second best is HST, and third best is LST. But in my personal opinion starting LST now would harm your yield as would HST and supercropping. Usually you want to have all these interventions planned while the plant is still in veg. Especially for an auto like mexican airlines that stiffens up pretty rapidly. Next time for HST what you do is you bend the lateral branches until they start to give off a sound, in this way the branch is not broken so the plant recovers faster and the height is controlled. I think you should run this grow without training because i noticed that autos once they're ready, if you f with them they will not be happy at all. You LEDs are fine, the plant can get real close to these with little harm, but honestly, only you can say for sure. Do that "hand test", that means measure the distance between the light and your hand and leave it there with the lights on, if it starts to be uncomfortable then it's too close to the plant at that distance. theoretically you could get as close as 8 inches. Plenty of space for your healthy plants ! Hope this helps ! π