Its pretty straight forward. The GC plates need to have the proper size bearing for the upper shaft to come throw for it to be snug. Below that you need to make sure you have your retaining ring which goes right below the strut housing in the wheel well. Its the circular plate to which the the three bolts come through to attach the GC plate to the strut tower.
Then, the last thing you need is to make sure you have the top spring insulator or spring hat. Its pretty straight forward if you take the time to look at either item
The most important thing here is to make sure you have the correct bearing which matches up the shock shaft OD to the ID of the GC plate's inner rotating bearing. Without it, the shaft will never fully tighten and it will eventually fail (more than likely a stress fracture failure)