Ford 2003 Mustang Workshop Manual page 1347

13. Remove the special tool.
14. Install the crankshaft sprocket, making sure the flange faces forward.
15. Position the LH (inner) timing chain on the crankshaft sprocket, aligning the copper (marked)
link with the timing mark on the sprocket.
16. Install the LH timing chain on the camshaft sprocket, aligning the copper (marked) link with the
timing marks on the sprocket.