Welcome to the forum. Since I'm a guy, I sure would like to look at some pics of your Mach 1.
This is what I installed to get tighter steering.
It's a manual steering center link. I'm an overweight, 63 yo out of shape guy with manual brakes and steering on my Mach 1. Who needs power anything on a classic Mustang?
As the guys have said, check all the connector joints in the steering. It usually takes two people, one turning the steering wheel, the other under the car observing and shaking joints for tightness.
Pics brother, I gots to see some pics. Oh, and which part of the world do you call home?