Originally Posted by Kurlon

Easy there armchair quarterbacks and internet rambos... There is a first time for every one. You all didn't drop from the womb knowing about circlips.

So, look at the side of the piston. You'll see a hole through it, that's where the wrist pin hides. On each side are two spring metal clips holding it in place. There are a few different styles, but the idea is the same, the wire sits in a groove milled into the piston, preventing the wrist pin from sliding past. Remove one clip, and you can use a screwdriver to push the wristpin out from the other side. With the wrist pin out, the piston will lift off the connecting rod.