Bought this kit for my 2005 Tundra quad cab 4x4. Leveling blocks are good quality CNC aluminum about 1.125" thick. A lot of the reviews talk about the ease of installation. Maybe for some truck models, but not so easy for the Tundra. Here are some pointers to make the job go easier and faster: 1. First things first, once you remove the strut assembly and before you install the spacer you will need to grind approximately 3/8" off of each of the strut mount bolts on the top of your strut so that they will sit flush or below the top of the spacer which bolts back into the upper strut mount in the wheel well from the top. 2. Everything I read said to drop the rear mounts of the lower control arms to make installation of the lower strut mount easier. BS. This cannot be done on the first generation Tundras without first removing the steering control arms as the rear bolt on the suspension control arm cannot be removed unless the steering control arm is first removed. You do not need to remove either nor do you need to remove the skid plate (saw a number of sites saying to drop the skid plate too. Needless hassle all the way around). 3. Instead, you will need to remove the four bolts that attach the ball joint assembly on the lower control arm to the wheel hub. This, along with unbolting the outer bolt of the upper control arm, tie rods and other little bits holding the suspension assembly together (including unbolting the ABS sensors), will enable you to move the wheel hub assembly to one side while you leverage the lower control arm down. I literally had to stand on the passenger side and press with all my might while my wife fought to get the lower mount bolt installed. However, this is the secret to getting the movement and leverage you need to get the lower strut mount reinstalled following bolting the assembly to the top mount. Notably, none of this is easy as this little spacer block maxes out all available vertical space between the upper strut mount and lower strut mount, plus some. 4. When unbolting the ball joint assembly you will want to place your floor jack under the ball joint bolt under the lower control arm and jack up the suspension several inches to relieve the tension on the assembly. Once unbolted you can remove the jack. Now the lower control arm has it's maximum range of motion AND you can get the hub and brake assembly pushed over to the side so that you have more work space and a better angle to work from. Reassembly will go in the opposite order, but first there will be a herculean effort to leverage the lower control arm down far enough to get the lower strut mount back in the mount on the control arm while a second set of hands installs the strut mount bolt. I had my wife quickly place a 3/8" steel punch partially through one side of the mount to hold everything in place. This gave both of us the opportunity to rest a little and the punch made a nice lever to help her line everything up and finesse the bolt in from the other side. Once all that is done you will need to use the floor jack again to jack up the outer portion of the lower control arm so that the ball joint assembly can be re-bolted to the hub assembly. You will need to raise this up a good 4-6" to get the two assemblies to line up and be close enough for the bolts to thread. Since this is a vital part of the trucks steering and control you want these bolts as TIGHT as you can manage when reinstalling. I laid down to ensure I had as much leverage as possible when tightening.5. Regardless that you did not drop the control arms you will need to have the truck aligned right away as the spacers affect vertical tow, angling the bottom of the wheel inward by a good inch or so.If you follow these instructions you'll save yourself hours of grief. Took me about three frustrating hours of playing with spring compressors and all sorts of other nonsense on the first side before I happened on the idea of ubolting the ball joint assembly from the hub. Other side took me less than one hour start to finish with no busted knuckles (busted a bunch trying to figure out the first side). Happy wrenching!