Yes, an early steering box, and must be A or B body. C-bodies had the "large sector" shaft which later A's changed to (don't recall year, Dan does). I have a box from a 67 or 68 Satellite that I recall is "small sector". Pretty sure I saw rebuilt gear-boxes on rockauto for my 64 or 65, and some are "core charge" so you can just eat that (<$200 total?). Hardly extra cost, since shipping one back would about equal the core ($50?). Don't buy the "send yours in" choices.
I think the Pitman arm is the same for manual and power steering, but verify. If for some reason, you change other steering parts, a V-8 center link will fit a slant (not vice-versa) and would have you set if you ever go V-8, LS, diesel, whatever. Even then, the V-8 link slightly hits 1967+ V-8 small block oil pans, but a hammer blow can make room. Don't even think of trying later A steering linkage. They are totally different (inner tie rod studs different direction) and for wider cars.
You will need a shorter steering rod, or the whole column, but people here will trade you even or even pay for your manual column, because so many change to engines and headers that don't work with power steering. If you change the whole column, consider what shifter you want (floor or column). I recall some just cut their rod shorter and welded, but I wouldn't trust my welds for that.
If you want AC, one "kill 2 birds" is to get the bracket kit from a Volare or Aspen that had a Sanden compressor (all hot rodders use). I got one at the junkyard cheap. It mounts a Saginaw pump on the outside, which is the preferred pump (more efficient and easier to source, i.e. GM). You will need to customize your hoses, but I had to do that even going from a TRW to Federal pump (different fittings). I took just the valve body from a later p.s. gear to match the hoses, but most hydraulic shops could make a hose. I think all Saginaw pumps used O-ring fittings. Note that even the factory early-A & B h.p. hose is kind of custom w/ two sizes connected with a crimp coupler.
