Where to set the fuel injector timing marks on a 6.5 diesel motor?

On a 6.5 diesel engine, the fuel injector timing marks should be aligned according to the specific timing procedure for that engine. Typically, this involves setting the engine to the TDC (top dead center) position of the compression stroke for the number one cylinder. The timing mark on the injection pump should align with the corresponding mark on the engine's timing cover or block. Always refer to the manufacturer's service manual for precise details and specifications.