Can you post some pictures of the target assembly. I have my F2K target bank tore down right now. I am having similar issues. My reset bar was broken at some point and someone added a big hunk of steel and brazed the bar together. This has caused the side of the target assembly to wear. The reset links are also worn now. I have rebuilt several target banks. I can tell you that all metal parts need to be clean. The metal stern and bally used oxidized and that oxidation causes drag. Lot of times I will tear target down and bead blast it. Make sure the ledge that the target sits on that is pulled by the solenoid is flat. If it is bent the target will slide off of it. Make sure they are clean and no oxidation is causing lip of target to stick to edge of that ledge.