The steering gear is pretty much the same so long as you keep to the "small sector" output shaft. The large sector shaft came out somewhere in the early to mid 70's. What I can find on Rockauto, there wasnt a different between the different body styles, engines and the steering gears
The steering column shaft is shorter for a power steering car than it is for a manual steering car. So you will have to find a power steering column and use that or take it apart and use the steering shaft in your column.
There is a difference between manual and power steering couplings. The input shaft on a manual box is a larger diameter spline than a power steering gear input shaft.
Pitman arm MAY be different. PST have these listed. But I cant remember if it was different between power and manual steering.
The power steering pump is a little tricky as well. There is a saginaw pump, the federal pump and the TRW pump. The saginaw pump will not work, found that one out the hard way. The TRW and federal pump will work, you just need to figure out a little more information on when your engine was made. Around the time your car was built Chrysler switched from the TRW pump to the federal pump (I believe, they may have switched in 67). I forgot where i found information on casting numbers and such to determine which pump would work... But I do know you can get new power steering pump brackets for a big block for the TRW and federal pumps. So you can get one of those pumps off of any body or engine and just change the brackets to big block ones.
you also need to find the power steering pump crank pulley. I believe any pulley from around the same time period from a 383 would work.
the power steering gear will bolt up to your K frame. They did not have power steering and manual steering K frames.
You then also have to get the power steering lines and belt.