So I just finished my Z H-Tech spring intallation using this DIY and I can say that this is a great DIY, highly recommend reviewing it a few times prior to starting a spring/shock install.
Here are some additional points I would make based on my experience:
1. The rears are very easy, it took me about 20 minutes to do both rear springs. This is good, but also bad because it instills a false sense of confidence as you head to the front...
2. I struggled with EVERY nut and bolt. They were all difficult to remove. Even the little 12mm nut holding the brake line on the strut was a pain. I thought at one point I was going to break the bracket off the shock. This stuff was my best friend:
I used PB Blaster on all the nuts and bolts and it really helped. But you gotta be patient and use some muscle 'cause a lot of these nuts did not want to come out.
3. I realized after the first side, that if I jacked up the lower control arm (right underneath the bolt that holds on the shock/spring assembly), it made it easier to compress the spring with the spring compressor. When you jack it up you're already compressing the spring. Once you jack it up and put on the spring compressors, you let the jack down and it's much easier to get the lower spring/shock assembly bolt out. Play with the floor jack a bit and it's actually pretty easy to get the sway end bolt out.
4. Of the 4 hours I spent on the front, about 3 of those hours were spent trying to remove the nut that sits in the center on the top of the shock assembly (the one shown in the DIY where the OP uses the crescent wrench and 17mm box-end wrench and the foot on the assembly). That SUCKED!!! I knew that it was going to be a problem for me because that nut/bolt was really rusty looking. But here's the real problem: once you get the nut to the point where it's almost off, you can't use the crescent wrench to hold the "bolt" steady while turning the nut. The "bolt" is actually the shock piston shaft, so it spins as you're trying to remove the nut, and there's no other place to keep it from spinning. So I ended up using a ton of PB Blaster, turning the nut until the center bolt spun, then re-tightening the nut, then lossening, more spray, back and forth with loosening and tightening, for what felt like forever. Biggest pain of the whole job. I don't know if anyone else had this experience but I'd be interested to know if anyone figured out a "trick" for this. I could not and instead I just kept at it, wanting to kill someone or break something out of frustration.
Other than that the DIY sums the whole thing up really well. It's not "easy", but it's do-able if you are somewhat mechanically inclined and have some patience.
