I made the mistake of having 4WPW install my 4" lift 'cause I didn't have the time... I took out the add-a-leaf they installed in the rear of my '88K5 and found out the center bolt was completely stripped and all the springs were floating around! They did my friends '89 Sub at the same time they did mine and when he got home he discovered they didn't put the nut on one of the front shock bolts, 1 of the 2 shocks on the drivers side was already dangling w/ the other one ready to fall off!!! He brought a friend to the shop last weekend to get a lift installed on his TJ, when they arrived to pick it up there was some kid who was pissed off since he was the last one there and they saw him stripping some of the bolts out of frustration!!! I will never let them install anything of mine again! If I don't have the time, it's gonna wait!