Personally I think you have a road to hoe before you worry about a Borgenson box. The handling personality of these cars is changed DRAMATICALLY by doing a few simple things
1....ALL of the front end moving parts MUST be brought up to "factory new tight" standards. This means good quality ball joints, all rubber bushings, tie rod ends, and the pitman and idler arm
3...use good radial tires. Even good 14's are a huge improvement over what we had in the 70s
4...Get it aligned to "modern tire" standards. This has been discussed here MANY times
5...Get better / heavier performance torsion bars. I'd say "in today's world" even the heaviest bars Ma originally made are barely adequate
6...Run a front anti--sway bar, either factory, or aftermarket. Hochkis and others make them
My own case is an excellent example. My 67 started out no sway bar, stock suspension, tiny brakes, "floppy" tires. You'd wiggle the wheel and the front fenders acted like they were water skiing. After the above additions, "horsing" it around a corner results in NO fender dip, and it goes where you point it.
THEN see if you absolutely "must" have a faster steering box.
FORGET getting rid of the T bars. Unless you are doing some wild engine swap, it is competely un-needed.