The newer car has rack and pinion steering - a different system.
Steering can be made lighter. The first way is to add a couple pounds of
air to the tires - all of them so the front / back slip ratio is
maintained. If specification is say, 27 Front and 30 Rear try 29 /
The front suspension geometry is adjustable, specifically the caster
angle. Decreasing it while remaining within the specification range will
reduce steering effort and make the steering feel lighter.
All that said, perhaps she really just wants a newer car, the 1990 is
now 14 years old.