Power Steering Upgrade and questions

[Nima]

Hi There:
Here is the story:
Few years ago I picked up a complete set of power steering gear, pump, bracket and lines from a junk yard to upgrade my 67 C20 2wd. For some reasons I never got around to do it until now. Now, I have forgotten what model year the donor truck was! (I must be getting old!). These are my questions:
- There are casting number on the steering box (7802644) and then there are # on the steering box cover (7812145 and 01871). Based on the casting number it seems this is a box from 80-85 truck, is this correct? What the other numbers mean? How can I decode them?
- The steering pump has v grove pulley. Does this fit with the 80-85 trucks?
- Is the pump bracket something that I can use? Some pictures of your power steering pump and bracket would be very helpful.
- Do I need to replace the rag joint or can I reuse what it is on the steering box?
- How about the pitman arm?

I looked at FAQ but I really couldn't find the answer to all these questions. If I have overlooked them, I would appreciate if you point me to the right direction.
Thanks