If you have not been a ford tech for @ least 10 years doing this particular type of timing chain replacement do not attempt this on your own. If this is the dual chain application it is next to impossible to change. It would be easierwith the alignment tool for this job but even then it will never run right again. I promise u that. Worst possible design ever in an engine.U either have a good one or a bad 1 that easy. R u possitively sure its the timing chain?