Coilovers would replace the torsion bar, Heidt's builds a nice one. There is a bit of geometry involved in figuring A-Arm lengths, spindle heights, and push or pull rod lengths. The length of these componets will effect the camber and caster. Placement and mounting height along with tie rod length on the rack and pinion will become critical to setiing the bump steer. You can draw it out and chart it on a graph, or I'm sure there are programs available that will do it for you.