On my 85 380SL the plastic guide rails broke and caused a no start. On the right head 3 rocker arms are loose. Is it possible the rocker arms bent and not the valves? I took a height measurement of the valves and they are the same as the valves with tight rocker arms. And I took the measurement with the cam lobes opposite of the rocker arms. The engine has 100 k miles and ran great. If the valves are bent would it be wise to replace the bent valves, all rails, and timing chain before doing a complete rebuilt?