72 Duster Info

Okay guys, who's out there board out of their mind and has the need to share information?  I just parked my 72 duster in the shop for the big project after having it in storage for 16 years.  It came with an automatic slant six which is removed.  What I want to do is build a 360/automatic and am getting a list of what I need together.  First of all there is the K frame...do I need a smallblock K frame and what years will match?  Then it has drum brakes all the way around.  What can I get parts off that will bolt on to what I have?  Maybe I could find a whole package of disc brakes and K frame together??  I have big bolt rally rims with big bolt pattern, and my car is small so I want to switch front and also find an 8 3/4 for the rear is possible.  Is there any other good rear-ends like Ford 9 inch?  I may have a couple but don't know what will work.  Well, I think that's enough for now, I'm sure I will have more in the future.  Thanks to anyone out there who can help.  I can't wait to get started.  Thinking about building a rotiserie for the body!!!