Better option than a ground strap?
There is no reason to use a "strap." Just use a cable similar to the hot side. Ground the battery to the BLOCK. That is the highest current, IE the starter. Use another cable from the block to the firewall. Look at your alternator mount on the pass. side head. That/ those same holes are on the rear of the driver side head. Get a short 1ft or 18" Ford style eyelet to eyelet starter cable and bolt to the rear of the head and the firewall. The master cylinder studs sometimes work well. The unibody is completely welded. Some guys claim that the welds are poor for electrical, and that is nonsense. If the welds are that poor, you better worry about the car breaking into pieces!!! Lots of little spot welds add up to lots of "surface area" so to speak.