Do you have the original engine in your car? My understanding is that the solid lifter engines (340 and 360hp) have a pan that holds an extra quart of oil, and extends downwards a bit more in the front section (than the 250 and 300 hp hydraulic lifter engines), and will/may cause interference. Probably for that reason, the power steering option could only be ordered with base and L75 engines in 63 (and besides, someone ordering the car for high performance didn't want extra accessories robbing that engine power).
I think, too, that the linkage moves a bit because it is partly attached to the unsprung suspension (A-arms), so a static clearance that looks adequate in the garage may not be adequate on the road when the A-arms hit their upper bump stops.
