You can achieve what ive read as reasonable results with a modified K frame (horns extended back to mount the rack)
and a GM manual or power rack
the aussies use a variable rate Holden rack from an 80s-90s commodore (which is a magnum style car)
issues
1) six cylinder and you can mount the rack high enough to get the ends parrallel to the ground at normal ride height
2) 8 cylinder you can't which means excesive bump steer
3) the eyes in the steering knuckles/ spindles for the balljoints on the end of the rack will be in inches and the rack will be in mm so you need to cut a new taper
4) the rag joint in the column needs to go an the end of the column shaft needs some arrangement attached to connect to the rack.
avoid if at all possible a cradle mount that runs from chassis rail to chassis rail. they flex badly only 1 company makes these and i have not heard a good word said. (oh just had a look at the link above....these are the guys to avoid)
manual and power style boxes for aussie cars have great parts compatibility with US boxes
differences exist mind
One box has its pitman arms facing forward
the other has it facing back
so the master spline on sector shaft will be in different place
and it must mean the ballnut and screw works in reverse. i think. i can't picture it.
but they are rebuildable and use bearings and seals that are still available.
stering box
http://www.pentastarparts.com.au/sunsho ... ail&p=1117
rack kits
http://www.pentastarparts.com.au/sunsho ... ail&p=1699
Dave