Why would you want power steering? It's heavy and not necessary on an early A. The original Formula S cars came with 16:1 manual steering only, and if you read an original road test, it was praised.
Fast ratio manual boxes are not that easy to find. Most people would want to use a "granny" manual box anyways, since its easier to steer.
Don't use a fast ratio pitman (T/A) arms unless you can buy the matching idler arm. The original T/A's didn't have a matching idler arm. It was a flaw.