Power Steering opinions wanted for 1937 Buick Roadmaster

[Mutt's37Buick]

I'm selecting the power steering set-up for my 1937 Buick 4dr Roadmaster. The front suspension will be rear steer like original, but with some parts swapped to add disc brakes and ball joints. Here are the PS options I'm considering:
- 1988 Cavalier Rack & Pinon as described in: http://www.crankshaftcoalition.com/w...inion_steering
- GM 605 Steering Box
- 1995 or earlier GM Van Power Steering Steering Box
I've read the Rack & Pinion will be the most responsive.
1) Can anyone share experience with these options with regards to responsiveness and/or difficulty of install?
2) The Cavalier Rack & Pinion has the attach points for the Tie Rods at the center of the rack. (see below). Does anyone know of other racks from a different vehicle/make that has this arrangement?
3) Is installing a GM 605 difficult and are there instructions available?
Thanks