How should my duster handle

Just drive in a straight line at 2 speeds ya do not need assist.

Speed one Go

Speed two Stopped

If a third speed is needed get factory power steering.
A factory power set up is not going to feel like over steer but I run 15 inch 60 series on my cars front since the 70s.
There is a good between racing a car and just tooling around in one.
Skinny tall tires move easy. Short fat ones don't.
If you go fat fronts keep the power steer. Don't make a cruiser unpleasant or you will crusie it less
Your opinion may vary, my opinion may be stuipd but I never ever claimed to be smart.