Forget what the manuals say about radial tires. The tires they were written about haven't been available for decades. One might as well insist on 1970 fan belts and 1964 engine oil.
You have power-steering A-bodies...and you find them excessively hard to steer?

Something's definitely wrong, and it's not radial tires making the problem. Could be problems with the steering system, could be you haven't tried radials on an A-body in forever and the ones you picked were no good, could be the ones you tried were OK but the car's alignment wasn't set up correctly. Radial tires are a lot more directionally stable; by contrast bias-ply tires want to wander all over the road. Maybe that's what you're detecting, sort of, but wandery, floaty, squirrelly steering isn't better or safer, even if you think you prefer it.
When you get the car set up correctly, you'll have zero trouble steering the car easily with one finger on the steering wheel. Again, there is no genuine way in which bias-ply tires are better. This goes for bone-stock A-bodies, too, not just cars upgraded for better handling.
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Too many people who were born on third base actually believe they've hit a triple.
