I agree with this, I always thought that I needed power steering but after test fitting my 390 even with a big block & 17x8's up front I could stand outside the car while reaching in & turning the wheels from lock to lock with one hand. Decided just to keep the manual steering setup, rollerize the idler arm, & pack the steering box full of grease.Unless you are running wide tires, the oem system is really very easy as far as steering effort goes and power is really more of a luxury item versus a "gotta have"
These will make a big difference along with a proper alignment and good tires. Here is a good starter article and add in the 1" Shelby drop to make it steer better by putting the tires flat on the ground too. Roller spring perches are a big improvement also. What diameter is your steering wheel? Many originals have been replaced over the years, a smaller wheel will increase input.rollerize the idler arm, & pack the steering box full of grease.