R&P for A-bodies

There's quite a few kits nowadays to convert the A-body to R&P steering---and all of them expensive, IMO. But back in the day early P/S cars had R&P using over-the-counter parts & retained the torsion bars. Anyone know how to do it or have good detailed pics?
I'm trying to clone an early P/S car and would like to make it as accurate as possible.