Just broke night last night to do this install. Had a few hitches due to lack of tools, as I needed more than what the how to's recommend for the rear. But luckily I have night dwelling friends like myself. Actually it was the endlinks, paticularily the rear ones that gave me a hard time. I was impatient I guess. I sprayed some wd40 on them, smoked a cig, and decided to goto work on them. Well the threads kept turning with the nut. So I had to find a regular 14mm wrench instead of using my ratchet, then had to have my friends try to find me an alan key set so that I could use it to stabilize the thread while I wrenched the nut. At frist I tried with bare hands, thinking "I'm so manly", and the alan key and wrench bruised and drew blood from my palms after many pathetic attempts. Eventually I sucked it up, put on some work gloves, wrapped each tool in a work glove, and got that 1st rear endlink off within a minute. Another thing that gave me trouble was my right rear. The bolts holding the shock to the rotor were put in from the rear to the front, meaning I couldn't pull those out due to the caliper being in the way, so for the right rear only I had to remove 2 bolts from the caliper and let it hand down. When putting everything back together, I put those bolts back in front to rear, just like how the left rear has it, just in case I ever have to do this again. I'm pretty sure that should be fine even though its not how mazda did it, but if it isn't, someone please correct me. I didn't need spring compressors as someone had suggested, just good ol' human labor was enough, though that may've been the cause of unneccesary blood and sweat. For those suggesting a professional, the only reason I could see someone finding one is 1: lack of tools and time... 2: laziness... 3: abundance of money. This was a straighfoward project, even for a beginner like myself.
But other than that, everything was rather straight foward. When the sun came up, I was just finishing up, after maybe 6-7 hours or so, and took it out for a spin. Yes, I started doing this project at 12am in the morning, under a street light, a ghetto spotlight, and two mag lights. At around 3am actually someone from my highschool wrestling days just happened to pass by, and stopped in his civic and loaned me the wrench I needed from those damn rear endlinks.
Ride harshness is definitely noticeable, but so is much more easily attained oversteer. I didn't have any noise issues with clunking as such, even without using extra washers like the thread garrets77 mentioned. I'm going to let the springs settle for at least a week, probably two before going in for an alignment. I guess that wraps up my biggest project to date. My hid install couldn't even compare, that didn't even take an hour.
edit: forgot to mention, there is one thing thats got me completely stumped, my rear left selt belt, its locked in place and I can't pull it long enough to put it back where it belongs, so right now its just bouncing around in my trunk. I had the same problem with the right rear, but after messing with it continuously for a few minutes I got it to unlock, but I can't seem to do it with the left one. If someone could give me a fix for this, that'd be great. If not, of well, my rear passengers never wear belts anyway.