I tried to install power steering in my 71 140. Got most of it done but ultimately it was unsuccessful. As I remember it, the power steering box mated right up as did the drag links although I think I had to reuse the pittman arm from the manual steering box. Not entirely sure about that detail but it will become obvious as you put those pieces together. The power steering pump got mounted where the idler pulley goes on cars with AC. The hoses and overflow container can be mounted based on what you have. Just make sure the overflow container is higher than all other components, pipes, pump etc. The bracket for the pump requires 3 mounting points one of which is a hole which was not drilled in my engine head. There was a boss but no hole. If yours has that hole you're all set. If not, one can be drilled and tapped.

The real problem for me was an inability to construct a steering column of the correct length with a mounting on the upper end to which I could attach the steering wheel and hardware for the directional signals and a mounting at the lower end which would mate up with the short offset shaft with two universal joints and the breakaway rubber bushing. By the way, for this project I was using a combination of parts from a 140 and a 164. Hopefully you will have better luck.

Also, I have replaced carpet in a 140 and a 160. I bought flat auto carpet, padding, a few sharp razor blades and some 3M spray glue. Its a slow tedious process to fit, cut and seam but it looks fine. I could not find anyone who has molds to mold a new carpet set using polypropylene backed carpet. The only other choice was to have someone cut and sew a carpet set using the old one as a pattern. This seemed expensive and likely to be less than a satisfactory fit.