When we decided to do steering linkage replacement as a stand-alone article outside of complete front suspension replacement, we questioned our own judgment because front-end components typically wear out together and are replaced at the same time. However, Mustang front suspension components also have a lifespan that depends on how the car is driven. Upper ball joints are high-wear items on classic Mustangs no matter how you drive them. Uppers are normally the first front suspension parts to wear out, even if you're running the best high-quality Moog parts. Lower ball joints virtually never wear out because they're not carrying the same kind of load as the top. Tie-rod ends vary in lifespan depending on how you drive. If you do a lot of city driving, tie-rod ends wear quickly, as do idler and Pitman arms.
So we're taking this opportunity to focus on the steering linkage. Classic '65-'70 Mustang steering linkages differ depending on power or manual steering and the model year. Although linkages in '65-'66 Mustangs are similar to '67-'70 Mustangs, they're different because the later Mustang has a wider track. That's what makes '67-'70 Mustangs feel different when you drive them. The '65-'66 Mustang is closely tied to its Falcon roots with the same basic shock tower stampings and steering linkage.
First-generation '65-'66 Mustangs with manual steering have a solid centerlink (also called a drag link) from inner tie-rod end to inner tie-rod end. Inner and outer tie-rod ends are identical on both sides. With power steering, you have a different centerlink that is also an integral part of the power steering control valve. That means the control valve and centerlink are the same. Inner and outer tie-rod ends are different on power steering cars to clear the control valve.
Another consideration is six-cylinder versus V-8. Sixes have a different centerlink and Pitman arm than V-8 models because the centerlink takes a dip beneath the V-8 oil pan. The six-cylinder centerlink is straight. Try to use a six-cylinder centerlink on a V-8 Mustang and you can expect frustration and impossible fit.
For '67-'70, Ford simplified the Mustang steering linkage with the same inner and outer tie-rod ends for both manual and power steering. However, the centerlink for manual steering is different from one for power steering. Unlike '65-'66, the power steering centerlink screws into the control valve, where it is pinned for security.