I currently have a stock steering system (manual, 19:1 ratio). What would it take to convert to power steering? How much? What about power rack and pinion?
assuming you are talking about a 67 stang, you can use the power assist steering system from a granada as it bolts in, centerlink and all. if you have a 65-66 mustang you can use the maverick steering linkage.
Just as a side note, if you are currently running headers, or plan to later, you will likely need to get a relocation bracket for whichever power steering system you decide to go with.