I have a Steer and Gear Stage 1 in my 70 Coronet with power steering. Its a huge improvement over stock. However, If I had it to do over I would easily go stage 2 and maybe even stage 3.

Best of luck ...

One more thing, having rebuilt the upper control arms with offset bushings, I can dial in an alignment of 2.5 degrees of caster. This along with the stage 1 box makes the car feel 100 times better than stock.

However, If I had it to do over again, in addition to the stiffer steering box I wouldnt even fool with the stock upper A Arms.
Get a pair of the aftermarket arms which can dial up to 7 degrees of caster. The hotchkiss are really nice but very expensive. Firm Feels
arms would be great...

Granted my car is just for street driving (no racing) so the more caster, the better the car tracks and feels on the highway. Most newer cars have caster at 4 degrees and higher BTW.

Also, go with stiffer than stock torsion bars