Something that I don't understand about check chains in general:
The attachment point of the check chain or whatever is usually not in line with the front pivot on the lift arms. This means that the chains will get tighter or looser when the implement is raised. Sometimes the attachment point is lower than the front pivot which will cause the chains to tighten when the implement is lifted. If they are already tight when the implement is in lowered position--will they prevent the implement from raising all the way up? If they are a little loose when the implement is lowered--will they tighten when the implement is raised to prevent side sway when turning the tractor?
The check chains mount to a bracket that rotates on the same shaft as the front pivots on the 3-point arms, so the chains do no tighten or bind as the 3-point is raised and lowered.