I have all the tools I need and am going to get those hole saws off the ebay link you posted,and my plan for the return was also over the back and splitting it into lockline nozzles and piping. OK seems I have my plumbing plans locked into my brain and can fly with it, the Lighting is a breeze, already can redo my MH and may go T5 for supplementation. My next obstacle is building the stand and canopy. I have all the high end tools but I am by no means a carpenter, for me electrical/lighting can do that asleep, plumbing no big deal, welding easy, carpentry ouch