So step 1 is 95% complete! The inside removal was not to bad just took some time to find the screws and bolts and the whole top unit came out as a whole. I bet it weighed 100 lbs! When it came to cut the cooling line I was on the scared side of things ie freeze skin or the gas kills me. So what I did with that was kinda crimp the copper line so when I cut it it could not all burst out. It did not work like I was hopping . I put 3 towels over the part I was cutting and just wiggled the same place and it ripped open. When it ripped the hiss made me jump back but it only hissed for 5 sec and I guess the oil that was on the inside made a small mess but the towels caught most of it. I am going to dry fit all of the parts tonight when my lights turn on in my other grow area. The way I am going to cut the holes for vents is a 4 1/8 inch hole saw. Since all my fans are 4" well i currently only have 1 4" inline exhaust fan but the other that I want is going to be 4".